Ronald Acuña Jr. 's alluring blend of power and speed pushed him into the consensus top-three picks in leagues last season. While fantasy owners try to discern how his plate discipline may affect his ceiling, there's no question a healthy and productive Acuña Jr. remains a top target for 2021. Despite playing through some nagging injuries during the truncated 2020 season including his wrist which affected his playoff performance, Acuña Jr.'s power trajectory continues to point up. 

Acuña Jr. logged 46 contests in 2020 accruing 202 plate appearances with 46 runs, 14 home runs, 29 RBI, eight stolen bases and a .250/.406/.581 slash line. Both his walk rate and strikeout percentage rose along with his isolated power. It's curious to note Acuña Jr. only recorded two stolen bases over his first 27 games then six during his last 20 while reading this quote from The Athletic in an interview with hitting coach, Kevin Seitzer:

Between August 15th through the 25th, Acuña Jr. missed 11 days due to a wrist injury which affected him until the end of the playoffs. This caused another collapse in batting average in September for Acuña Jr. who seems to wear down at the end of the season. Although he became more active on the bases, his isolated power ticked down in September despite hitting nine home runs but his .235 average within this sample depressed his batting average in such a short sample size. 

Delving into his Statcast data last year, Acuña Jr. recorded 100 batted ball events with 16 barrels (16 percent), an average exit velocity of 92.4 MPH and a robust 57 hard hit percentage, up almost 10 percent compared to 2019. Acuña Jr. also registered a sweet spot percent of 34 with an expected batting average of .254 suggesting his quality of contact slipped compared to past results. 

This resonated in his discipline marks on Statcast where Acuña Jr.'s zone swing percentage fell by 5.3 percentage points and his zone contact rate also fell by 3.2 percent. His chase contact (outside the strike zone) increased slightly despite his chase percentage going down. Transitioning to his swing percentage, Acuña Jr. reduced it by five percent but his whiff percent grew by 2.2 percent to 29.9 on the season. 

Acuña Jr.'s batted ball types remained fairly stable with a ground ball percent of 36, a fly ball percentage of 27 and a 29 percent line drive rate. Noting it's a small sample size, Acuña Jr.'s pull percentage jumped up to 43 percent while his opposite field percentage declined. Perhaps this manifested itself in Acuña Jr.'s last month when he launched the home runs with a low batting average. While many of these trends point to concerns, Acuña Jr.'s solid percentage of contact almost doubled going from 9.1 percent in 2019 to 18 percent last season and his barrel percentage remained stable. While many focus on Acuña Jr. as a power and speed player, his power may be underappreciated. 

Viewing Acuña Jr.'s percentiles from last year results in some eye popping numbers:

  • .401 Expected weighted on-base average (xwOBA) - 97th percentile
  • .590 Expected slugging (xSLG) - 96th percentile
  • 16 Barrel percentage - 95th percentile
  • 92.4 MPH exit velocity - 91st percentile
  • 57 Hard hit percentage - 99th percentile
  • 18.8 Walk percentage - 99th percentile
  • 29.2 Feet per second Speed - 97th percentile

To cast a wider net on his numbers, here's how Acuña Jr.'s last 112 games look from the second half of 2019 through and including last season: 

  • Acuña Jr. 2H 2019-through-2020: 505 plate appearances, 105 runs, 34 home runs, 77 RBI, 32 stolen bases; .258/.372/.552, 14.3 BB%, 30.1 K%, .293 ISO, .384 wOBA

Among qualified hitters in this time frame, Acuña Jr. ranks second in stolen bases, tied for second in runs and tied for fifth in home runs. It's worth noting his spike in strikeout percentage to 30 percent in this sample and needs to be accounted for when trying to predict his batting average in the season ahead. As for his spray chart in these 112 contests, here's Acuña Jr.'s line drives and fly balls courtesy of Statcast:

And his exit velocity with launch angle results to hone in on his batted ball results:

Given his recent results, it may be easier to predict 40 home runs over a full season compared to 40 stolen bases. Especially given the importance of Acuña Jr. staying healthy remains pivotal to Atlanta's success. 

Before displaying his projections from two different systems, Acuña Jr.'s first three seasons yields the following results:

  • Acuña Jr.'s First 3 Years: 313 games, 1,404 plate appearances, 251 runs, 194 RBI, 61 stolen bases; .281/.371/.538, 11.3 BB%, 26.4 K%, .258 ISO, .382 wOBA

Within his projections, the two sites' forecasts align a bit differently based on how they weigh Acuña Jr's outcomes. Steamer's appears more similar to his last three years data while ZiPS comes out a bit more aggressive to his more recent second half of 2019-through-2020 aggregates:

  • Acuña Jr.'s 2021 Steamer projection - 150 games, 683 plate appearances, 115 runs, 43 home runs, 100 RBI, 28 stolen bases; .279/.378/.553, 12.6 BB%, 25.5 K%, .275 ISO, .386 wOBA
  • Acuña Jr's 2021 ZiPS projection - 149 games, 672 plate appearances, 134 runs, 43 home runs, 115 RBI, 33 stolen bases; .282/.390/.568, 13.5 BB%, 25.4 K%, .286 ISO, .392 wOBA

Acuña Jr.'s home run total and batting average range of only three points do not leave much room for debate. It's more in the remaining counting statistic chasms in runs, RBI and stolen bases. Using this as a baseline, along with the unknown of how many games occur in 2021 due to a myriad of factors (pandemic, labor strife, etc.), here's how Acuña Jr.'s may result using a hybrid projection taking all of his results above along with his recent trends: 

  • Acuña Jr. over 300 plate appearances: 60 runs, 19 HR, 43 RBI, 14 SB
  • Acuña Jr. over 450 plate appearances: 90 runs, 29 HR, 65 RBI, 20 SB
  • Acuña Jr. over 600 plate appearances: 120 runs, 38 HR, 87 RBI, 27 SB

This projection set uses the following numbers per plate appearance: run (5), home run (15.7), RBI (6.9) and stolen base (22). Taking into account Acuña Jr.'s numbers throughout this profile, the most volatile category may be his stolen base results. Mining his career Statcast data, Acuña Jr. owns a .275 xBA through 852 batted ball results with 124 barrels (14.6 percent), an average exit velocity of 90.9 MPH and a 48.2 hard hit percentage. His xSLG of .565, xwOBA of .389 and xowOBAcon (expected weighted on-base average on contact) of .498 insulate his projections, especially in regards to power. 

For fun, ZiPS includes a number one comparison for a player in its team page of projections. Entering his Age-23 season, Acuña Jr.'s player: Jose Canseco. In case one wonders, Canseco's Age-23 season occurred in 1988:

  • Canseco 1988 Age-23 Season: 158 games, 705 plate appearances, 120 runs, 42 home runs, 124 RBI, 40 stolen bases; .307/.391/.569, 11.1 BB%, 18.2 K%, .262 ISO, .419 wOBA
  • Acuna Jr. 2021 Age-23 Season if 705 PA: 141 runs, 45 home runs, 102 RBI, 32 SB

There's only been four 40 home run and stolen base seasons in history with Canseco's netting him the Most Valuable Player award in 1988. Acuña Jr. hinted he'd like to make a run at this historic total but would Atlanta let him? Let the numbers below Canseco represent Acuña Jr.'s ceiling but his overall profile keeps him the number one pick conversation. 


Statistical Credits:

ZiPS courtesy of Dan Szymborski

The Athletic article by David O'Brien for Acuña Jr. quote by Seitze