The one stat that defines each Ray, Part II

We began looking at the one stat that defines each Ray in 2016-17 on Monday by looking at the infield. Today we’ll cover the outfield. Let’s get to it.

Steven Souza Jr. - Strikeout rate

DRB writer JT Morgan covered some of this already with his victory lap on Souza’s breakout, so we don’t need to dive too deep into the numbers here, but it is certainly worth mentioning at every turn just how improved Souza’s plate discipline has been this season. Although the walk rate may indeed be the more important of the two plate discipline metrics, the decrease in strikeout rate is what I believe is the leading contributor in the incredible leap in public opinion on Souza this season.

This is a player who is always going to be inextricably tied to the trade which brought him to the Rays, and he has managed to flip the narrative on that deal from debacle to maybe-a-win optimism. As our own Adam Sanford pointed out on Twitter recently, the trade has never looked better for Tampa Bay.

The increase in ISO and walk rate make the most difference on the actual field of play, but cutting that strikeout rate from 34.0 percent last season to 28.7 percent this season is big in the eyes of many fans.

Corey Dickerson - Batting average on balls in play

Dickerson’s .296/.341/.517 slash line for 2017 is still looking quite strong, but he has certainly not been quite the hitter over the last five-to-six weeks that he was in April and May. His wRC+ was 140 before the All-Star break, and it is just 85 after the break so far. August has been his roughest month so far, with a wRC+ of 23 in the admittedly tiny sample of August so far.

The biggest factor in Dickerson’s slowing down has been his luck on balls in play. Here are his monthly splits for BABIP and wRC+ since May:

There have been other factors at play (a drop in line drive rate in the second half and a slight tick down in hard hit ball rate each month), but the biggest factor seems to be that Dickerson was running a bit lucky for the first half of the season and is running a bit unlucky right now. That’s the sport of baseball in a nutshell, and the Rays should still be ecstatic with his overall performance on the 2017 season (3.0 fWAR; 129 wRC+).

Mallex Smith - xwOBA-wOBA

On the surface, Smith has been exactly a league-average hitter in 2017. His 100 wRC+ and 99 OPS+ paint such a picture. However, Statcast’s latest metric (xwOBA) thinks that Smith has gotten a bit lucky this season. xwOBA is a metric which uses Statcast data (exit velocity and launch angle) to assign a Hit Probability to every batted ball put into play across baseball. Using the historical data that Statcast has, each ball in play is given a comparable batted ball score and then these are accumulated to take defense out of the question (in theory at least).

Now there are some issues with xwOBA and one of the biggest is that it seems to completely ignore speed. If we assume that every hitter putting the ball in play has the same chance of getting a hit if they make the exact same contact, that is obviously flawed. If Mallex Smith and Wilson Ramos (the Rays hitter who is underperforming the most according to xwOBA) put the exact same ball into play, there a far greater chance that Smith turns it into a hit than Ramos.

That being said, there is still some reason to believe Smith is performing over his head a bit with the bat. His BABIP is .364, a good 40 points higher than his Steamer projected BABIP. Now Smith can still have plenty of value as the Rays fourth outfielder even if his bat slows down a bit, there’s always room for a guy with wheels like his off the bench, but expecting him to keep hitting at a league-average rate might be foolish.

Kevin Kiermaier - Games missed

A season after missing 51 games for the Rays, Kiermaier has once again already missed more than 50 games for the Rays in 2017 (52 to be exact). KK’s return is right around the corner, but his repeating injuries have to be a bit of concern for the club considering the team extended him through 2023 this spring. Now they hardly paid a fortune for the 27-year-old centerfielder, but if he can never stay on the field, it’s still going to hurt the bottom line.

When he has been on the field this season, his defense has seemingly been a bit off from its peak, with a month-long stretch that looked as though someone (or some thing) else had invaded his body. However, his bat has been right in line with previous seasons, with his walk rate still in the solid range it reached last season, a good sign for the long term. If KK can return fully healthy (there were rumors that he has playing hurt in the early part of this season), he could be the push the Rays need to secure a playoff spot.

Peter Bourjos - ISO

Bourjos has been an essential part of the Rays organization in 2017, as he has helped paper over the aforementioned Kiermaier injury for large swathes of this season. Bourjos has been right around replacement-level overall, which is basically what you’re hoping for when covering for an injury to a key contributor. Bourjos’ has been steady in the field, and his bat has been a bit better than expected.

This is a 30-year-old had an OPS of .656 over his past five seasons, but his OPS has crept over .700 this season thanks to some revived pop from his bat. Bourjos is sporting a career-high .183 ISO, which may not sound like much, but his 13 extra-base hits have all helped, and his five long balls are tied for the most he has had in a season since 2011. Bourjos is by no means a long-term solution in the Rays outfield, but with Kiermaier’s return right around the corner, Smith and Bourjos will be excellent options off the bench for Kevin Cash and the Rays.