25. Xander Bogaerts, Boston Red Sox, 74.6 mph
Compared with teammates Mookie Betts and J.D. Martinez, Bogaerts’s 2018 batting season may have been easy to overlook. In fact, he hit a totally acceptable .288 with a .360 on-base average, producing 45 doubles, 23 home runs, and 103 RBIs. He had never before driven in 90. The double and home run totals were also career bests.
He did it with improved bat speed. Xander Bogaerts produced a 90.5 average exit velocity, three mph better than his 2017 average. He also produced a very good 9.8 percent barrel rate.
It also represented a substantial one-season improvement from Bogaerts’ previous numbers. In 2017, his 87.3 mph exit velocity came with a 79.7 percent contact rate that matched his career average. In 2018 he raised that contact rate to 82.4 percent.
Since Bogaerts is only 26, it’s reasonable to assume there remains room for improvement, which could be a scary proposition for those rooting against the world champs.
If you like home runs, he also improved his launch angle, to an average of 12.7 degrees. Until 2018 he had averaged about 10 degrees. That doesn’t put him in the “majestic arc” class, and it’s not likely Bogaerts will ever be primarily a power hitter. But he’s gravitating in that general direction.