So, there you go.
"The main thing, it was more a numbers game than anything else," Mattingly said. "He's got options and we're in a little box. That's the primary reason. Secondary is, he's on a usage path that puts him farther down the road than he's ever been.
"It wasn't an easy one, like I told him. We've put the guy in high-leverage situations for a young guy, and his stuff always matches up against just about every hitter. At the end of the day, it's a numbers game for him with the options."
Withrow emerged from Mattingly's office after getting the news appearing a bit stunned, speaking briefly to a few teammates before leaving the clubhouse to make some phone calls.
The 2007 first-round pick has been literally unhittable by left-handed batters (0-for-27). The only glaring flaw is 15 walks in 59 plate appearances to right-handed hitters.
But with Wilson's inconsistency and Perez's May slump after a lights-out April, Withrow has been used frequently in the seventh and eighth innings. On Tuesday night, he inherited runners on first and second with one out in the seventh and escaped the inning with no runs scored. He was knocked around in Arizona on Saturday night for five runs in 1 2/3 innings.
Withrow's departure will put the onus back on Wilson, Perez and Howell to efficiently set up for closer Kenley Jansen, although League has been more reliable than anybody this year and could pick up some of Withrow's innings.
Ken Gurnick is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.