Can Braves’ Ronald Acuna catch Juan Soto in NL ROY race?

For weeks Nationals outfielder Juan Soto has seemed to be a lock to win National League rookie of the year. But now, with Braves rookie outfielder Ronald Acuna on an incredible run, perhaps Soto's march to ROY isn't so inevitable.

Over his past eight games Acuna, 20, has eight homers and two doubles among his 16 hits. He’s the youngest player to homer in five consecutive games and the youngest to hit five leadoff homers. On Monday, Acuna became the first player since Brady Anderson in 1999 to hit leadoff homers in both games of a doubleheader.

At FanGraphs, the ZiPS model gives Soto a 40.4 percent chance of winning NL ROY compared with 15.8 for Acuna. But, as writer Dan Szymborksi explains, predicting ROY is difficult because "the standards for rookies are applied a bit more haphazardly by writers" who vote on the awards.

Two writers in each NL city will vote on the award, with five points for a first-place vote, three for second and one for third. A poll of MLB.com reporters posted Monday gave Soto 31 of 32 first-place votes.

If ROY voters consider the more traditional numbers, then so far Soto has the edge in most categories.

For the season, Soto is batting .301 with a .422 on-base percentage and .548 slugging percentage. He has 15 home runs, 43 RBIs and two stolen bases in three chances. Those numbers are obviously very good for any player, much less a rookie.

Acuna’s slash line over 75 games is .288/.346/576. He has 19 home runs, 43 RBIs and eight stolen bases in 10 chances. Those numbers also are outstanding.

If Soto really is leading the ROY race right now, it’s tough to say what Acuna must do to catch him. That’s because, again, no one really knows which criteria each voter in the Baseball Writers’ Association of America consider most important.

Plus, some areas of performance, such as defense and base running, can be difficult to compare (Acuna has better metrics in both and the eye test agrees). Then there are the three major WAR formulas with differing inputs for defense.

And will Soto’s underdog status help his case? Acuna was considered the No. 1 prospect in baseball before the season, but Soto was at Single-A last year. Soto wasn’t really supposed to be in the majors now, much less aiming for ROY.

Acuna obviously won’t keep up his current pace, but there are signs that he will remain productive through the end of the season. To me, what’s most impressive about Acuna’s production this season is that he has done it despite poor plate discipline, and that seems to be improving.

In 289 plate appearances this season Acuna’s walk rate (7.3 percent) ranks 24th among qualified rookies and his strikeout rate (28.0 percent) ranks 29th. (Soto ranks first and ninth, respectively, and has amazing discipline for his age.) Per PITCHf/x fata, Acuna has swung at 29.3 percent of pitches outside of the strike zone with a 11.5 swing-and-miss percentage.

But Acuna has been more disciplined at the plate since the All-Star break, when manager Brian Snitker moved him to the leadoff spot. In 105 plate appearances over that span Acuna’s walk rate was 8.6 percent, and his strikeout rate was 23.8 percent. He swung at 23.8 percent of pitches outside of the zone with a 9.9 swing-and-miss percentage.

Per StatCast data for the season, Acuna has hit the ball harder than Soto (91.0 mph average exit velocity vs. 88.9 mph) and done so much more frequently (47.5 “hard hit” percentage vs. 38.5 percent). Acuna also hits far fewer ground balls: 41.8 percent vs. Soto’s 53 percent. Acuna should have a better chance of collecting hits when he makes contact.

If Acuna can maintain his recent plate discipline, he should get on base more often, which presumably would improve his chances to win ROY. Then again, if Acuna’s plate discipline slides, he might still win ROY if he keeps hitting homers because everybody loves those. It also wouldn’t hurt if the Braves remain ahead of the Nationals in the NL East race.

With Acuna surging, Soto’s candidacy for NL ROY doesn’t look so certain anymore.