The Bartender, as he was nicknamed in Seattle based on his previous career as a (you guessed it) bartender, has not been very good the last two years.
His K/9 numbers dropped rapidly from 8.71 in 2015 all the way down to 5.81 in 2017. That sharp decline helped spike his ERA from 3.19 all the way up to 6.80 in 2016 and 4.44 last season.
However, despite the struggles Wilhelmsen’s fastball velocity has stayed consistent at about 95 mph. So if he’s not losing velocity, what is going on?
The biggest change has been a spike in his HR rate, which has skyrocketed from his days in Seattle. Part of this has to do with his home ballpark, as switching from the spacious Safeco field to the friendlier confines of Globe Life Park (seven home runs in 21.1 innings) and Chase Field (four home runs in 26.1 innings) likely had an impact on how many balls left the yard.
Switching to the equally spacious Comerica Park should help the veteran return to form.
If Wilhelmsen can keep the ball in the park he can become a valuable bullpen piece again, even if his strikeout rates do not climb all the way back to their old ways.