by Ben Meron, Andrew Kelser and Danny Blumenthal
Editor’s Note: HSAC is excited to partner with Sportico, a new publication from Penske Media Corporation. You can read a summary of this article, as well as outstanding coverage of sports business and media, on the Sportico website.
In what world would Starling Marte make an All-Star team over Mike Trout? While Marte may lack Trout’s superstar talent, one thing elevates him above the Angels’ phenom: Marte is a five-tool player.
Five-tool players excel in contact hitting, power hitting, speed, fielding, and throwing. Scouts have used the five tools for decades, but no standard definition exists for each tool. Using advanced metrics, we created a method for determining the best five-tool athlete at each position and assembled these players into an All-Around All-Star team.
Measuring the Five Tools
Contact
Good contact hitters consistently put the ball in play, rarely striking out. Hitting for contact allows for the possibility of the ball finding a gap, a defender making an error, or runners already on base advancing.
A player’s contact rate is commonly defined as the percentage of at-bats in which the player does not strike out. At-bats are used in this measurement instead of plate appearances in order to exclude the effect of walks. However, at-bats also exclude sacrifice flies, which are instances when a player successfully makes contact. We modified the standard measure of contact rate to include sacrifice flies, changing contact rate to (At Bats + Sacrifice Flies – Strikeouts) / (At Bats + Sacrifice Flies).
Power
Many stats assess power, but most of them fail to capture true ability. Home run total is a widely cited measure of power, but it does not account for stadium differences. Exit velocity (EV)–the speed that a baseball leaves a player’s bat upon contact–is also a flawed measure of power because it does not include the effects of launch angle. A player who hits a ball hard into the ground will not help his team as much as someone who blasts the ball in the air.
A player’s percentage of barrels (out of total batted balls) more accurately measures power, since this statistic factors in both EV and launch angle. In order for a ball to be classified as barreled, it must have an EV of at least 98 mph and a launch angle within a certain range.
Speed
While several statistics measure running skills in baseball, Statcast’s Sprint Speed metric measures it most literally. It looks at a runner’s “fastest one-second window” on runs of multiple bases (such as first to third on a single) and when running from home to first on weakly-hit balls. The average Sprint Speed for all players is 27 feet per second, but significant variation exists across positions.
Fielding
For non-catchers, Statcast’s Outs Above Average (OAA) is an objective measure of fielding because it employs radar technology and cameras to gather positioning and motion data. OAA rewards fielders for making challenging plays and penalizes them for missing easier ones.
OAA does not exist for catchers, whose defensive skills are not as focused on running to batted balls. Fielding Bible’s Defensive Runs Saved (DRS) measures catchers’ fielding abilities by estimating the number of runs saved in the field and by framing and selecting pitches. DRS also measures runs saved by preventing stolen bases; however, since this metric is largely dependent on arm quality, which is a separate tool, we subtracted this stolen base component from DRS to measure the fielding tool for catchers. DRS also exists for outfielders and infielders, but we prefer OAA because it better accounts for defensive shifts and positionings.
Arm
There is no statistic that accounts for throwing talent across all positions. For catchers, Statcast’s Arm Strength measures the average velocity (in miles per hour) of a catcher’s fastest 10% of throws on stolen base attempts. For outfielders, the arms runs saved component of DRS assesses arm strength; this measure looks at how often runners try to take an extra base against an outfielder and how often the outfielder throws them out. For infielders, there are no publicly available measures of arm strength, so we calculated throwing accuracy by dividing a player’s throwing errors by the number of batted balls in his fielding zone.
Methodology
In order to qualify, players needed to appear in at least 82 games (more than half of the season) at their position. We determined a player “had a tool” if he was above average in 2019 relative to others in the same position. The player with the most tools at his position made our All-Star team. If multiple players tied for the most tools at their position, we used the harmonic mean of each player’s percentiles for the five tools as a tiebreaker. Unlike a typical average, the harmonic mean tends toward lower numbers in a set. As a result, it is better for capturing well-rounded players, instead of those who only excel in one area of the game.
Our Picks
Although no catcher was above average in all five tools last year, the Phillies’ J.T. Realmuto had the strongest arm among catchers, and he was also the second fastest. He just barely missed the fielding tool, ranking in the 45th percentile.
Realmuto was selected as a reserve for last year’s actual All-Star game, but interestingly, neither the American nor National League starters–the Yankees’ Gary Sanchez and the Cubs’ Wilson Contreras–made our top five. Sanchez was below average in contact, speed, and defense, and Contreras was below average in contact and defense.
Atlanta’s Freddie Freeman was the only five-tool first baseman last year, and is thus a decisive pick. Although he did not dominate in any category, Freeman posted strong numbers in every tool; in his worst tool, fielding, he still ranked in the 61st percentile. Out of all of the players in our sample, only Cody Bellinger ranked higher in each of the five tools. Freeman hit a career-high 38 home runs last year, and his strong barrel percentage (70th percentile) surely helped him along the way. Perhaps Freeman would have been even more impressive had he not suffered (and played through) an elbow injury late in the season, one that later required surgery.
The Astros’ Yuli Gurriel led first basemen in both contact and speed, pushing the sum of his five percentiles close to Freeman’s, despite having the second-worst barrel percentage among first basemen. The low barrel percentage is itself interesting, given that Gurriel hit a respectable 31 home runs last year.
Detroit’s C.J. Cron led the four-tool first basemen in harmonic mean, and he was merely one OAA away from being a five-tool player. This may be surprising, considering he is only a 1.7 bWAR player and analysts do not talk about him as a top-class first baseman. Given that he has been on four teams in the past four years, his own teams do not appear to value him highly either.
Interestingly, former All-Star first baseman Eric Hosmer was one of only four MLB starters to possess zero tools.
Before 2019, it would have been surprising to see the Diamondbacks’ Ketel Marte atop this list. However, he exploded with 7.2 bWAR last year and finished fourth in the NL MVP race. This was mainly driven by the 32 home runs he launched, which was more than his previous four seasons combined. Still, these power numbers were no fluke, as Marte ranked second among second basemen in barrel percentage.
Ketel Marte struggled on defense last year, splitting time between the infield and outfield. However, the team’s addition of centerfielder Starling Marte (more on him later) allows Ketel to settle in at his more natural position, second base. Look for Ketel Marte’s defensive numbers to catch up with his offensive output this year.
Looking to the next generation, Atlanta’s Ozzie Albies shows the most promise. The 23-year-old’s weakest tools were contact hitting and defense, but he still shows off talent in these areas. For example, his 189 hits paced the National League, and according to Fielding Bible, Albies ranked third in DRS among all second basemen.
The lineup of shortstops was very crowded, with versatile players from across the league in contention for the top spot. Surprisingly, neither of 2019’s All-Star starting shortstops make our team, as both Javier Baez (11th percentile in contact) and Jorge Polanco (-16 OAA, which was dead last among shortstops) had major holes in their game. Nick Ahmed edges out a spot on our team, helped by his sensational defense. Ahmed is a two-time Gold Glove Award winner, and he tallied 16 OAA last season. Despite narrowly missing out on the cutoff for power, Ahmed has shown growth in his power numbers, boosting his home run total in each of the last four seasons. If he continues this trend, the Diamondbacks, with Ahmed and Ketel Marte, may boast the top double-play combo in the league.
The A’s Marcus Semien matched Ahmed as the most talented of the four-tool shortstops (based on the sum of the five percentiles), but his -4 OAA ranked so low it took him out of contention. Nevertheless, other metrics value Semien’s defense more than OAA, and he was chosen as a finalist for the Gold Glove in both 2018 and 2019.
Two players emerged with all five tools in this group, but only barely. Anthony Rendon of the Angels–our top pick at third base–and Seattle’s Kyle Seager each finished in exactly the 50th percentile on defense, and Seager was in the 50th percentile for contact as well. Meanwhile, Matt Chapman had the opposite problem: he excelled in four areas of the game, but struggled to hit for contact. Therefore, he was relegated to being the best player (as measured by the sum of all five tools) who did not make our team.
Rendon continued to do it all last year, leading the league in doubles again while also playing solid defense. However, nothing can top his biggest accomplishment–piloting the underdog Nationals to their first ever World Series title.
Some might be surprised that Alex Bregman is not featured among the top five third basemen, given that he led the American League in bWAR and blasted 41 home runs. Given that Bregman hits many fluky home runs (he finished 240th out of 249 hitters in average home run distance last year), he may not be as strong as that home run total suggests. Due to his low barrel percentage and mediocre throwing arm, Bregman failed to make our final list.
Cody Bellinger, Starling Marte, and Mookie Betts make up our starting outfield. The 2019 NL MVP, Bellinger easily earned a spot on the team. He was, by our measures, the strongest five-tool player in baseball. Marte qualified for our team because he was the only other five-tool outfielder, although he barely made the cut for fielding (50th percentile) and power (54th percentile). Betts only possessed four of the five tools (missing speed), but he was dominant in each of the four, meriting him the final spot in the outfield. And while Betts isn’t an elite sprinter, he is an excellent base runner. When HSAC explored the five tools of baseball in 2017, Betts rated as one of the ten best baserunners even as he finished outside the top 100 in sprint speed. It will be fun to watch Bellinger and Betts team up in the Dodgers’ outfield.
Perhaps it is surprising to find that Mike Trout is missing entirely from our list of the top 10 outfielders. While he is among the best in several aspects of the game—ranking in the 99th percentile for power, for instance—Trout only possesses three tools, according to our study, due to his below-average fielding and above-average strikeout percentage.
Disclaimers
We had to make several difficult choices when measuring the five tools, as they do not have universally accepted definitions. The tool “hitting for contact” is sometimes referred to as “hitting for average,” taking on a slightly different meaning that emphasizes getting hits over putting the ball in play. We therefore considered using expected batting average as our metric for this tool, but decided against it due to its overlap with percentage of barrels (both use launch angle and EV in their calculation). Additionally, it was sometimes difficult to separate the fielding and throwing tools. For example, OAA implicitly takes into account the quality of an infielder’s arm when calculating how many outs he has saved. Nevertheless, we concluded OAA is the most objective measure of fielding, so we used it for all non-catchers.
We also had to make some tough decisions when forming our team. When quantifying how many tools each player had, we classified players as possessing a tool if they reached the 50th percentile for their position. In reality, there is little difference between players at the 48th and 50th percentiles of a tool, but this proved the deciding factor between some players making the team over others. Even though Twins centerfielder Byron Buxton outperformed Starling Marte on four of the five tools, he ranked just below the cutoff for contact. Meanwhile, Marte just reached the cutoff for defense, enough to snag Buxton’s spot.
We also required players to have fielded a position in at least 82 games to make our team. However, this cutoff caused some utility players to be ineligible at every position. DJ LeMahieu, for example, played 145 games last year, but did not amass 82 appearances at any position. LeMahieu would have rated above-average at second base in every tool except speed.
Conclusion
When selecting players for the All-Tool team, we first ranked players based on the number of tools they had and then used the harmonic mean as a tiebreaker. As a refresher, the harmonic mean is another form of an average, which skews towards lower values. Therefore, it emphasizes well-rounded players and ensures that even on their worst tools, the players we choose still do decently well.
For no player is this more evident than Bellinger, whose harmonic mean of 84.9 across all five tools dominates all other players. Even on his worst tool, speed, Bellinger still ranked among the top 25 outfielders. And at only 25 years old, he has yet to reach his prime.
Few players can excel in every part of the game like Bellinger. Even if they aren’t as well-rounded as the Dodgers’ star, some players can compensate for their weaknesses by racking up value in other aspects of the game. The following graph displays the players who are the “toolsiest” and have the highest combined score across all five of the tools.
Unsurprisingly, Bellinger tops this list too. However, two of the next three players on the list did not possess all five tools: Matt Chapman and Byron Buxton, whose struggles with strikeouts prevented them from being named to the five-tool team.
Four of the top six players in terms of the sum of their percentiles across the five tools made the all-around team. In the end, the top players at each position were J.T. Realmuto (catcher), Freddie Freeman (first base), Ketel Marte (second base), Nick Ahmed (shortstop), Anthony Rendon (third base), and Cody Bellinger, Starling Marte, and Mookie Betts (outfield).
Using Baseball Reference’s Wins Above Average (WAA), we can see how this team would compare to MLB squads from 2019. WAA is similar to Wins Above Replacement (WAR), but compares players to the league average. It is useful for estimating how a group of players, based on individual skill levels, would translate into a team record. Last year, the Houston Astros had the highest WAA total, with their starters combining for 20.1 WAA. Summing up the eight players in our team’s starting lineup, the All-Around All-Star team would blow Houston out of the water, with 29.5 WAA. If this team were supplemented by a league-average pitching staff, designated hitter and bench, it would excel. If we assume an average team would go 81-81, this team would be expected to win roughly 110 games over a full MLB season.
Now that’s what we’d call a fantasy baseball team.
Editor’s Note: If you have any questions about this article, please feel free to reach out to the authors at harvardsportsanalysis@gmail.com.
