Rupp's average exit velocity is down to 89.9 mph this season after averaging 92.2 mph last year, Todd Zolecki of MLB.com reports.
Rupp said he has been missing too many good pitches this season. He has more than doubled his walk rate from 2016, but he thinks that may actually be problematic. "I'm seeing the ball," Rupp said. "I feel I need to be more aggressive when I get my pitches to hit as opposed to maybe falling deeper into counts. I think I had success last year swinging earlier. I don't want to get to two strikes and start seeing 95 mph sliders." Rupp has been getting an opportunity to work his way out of his early-season slump, but he could start to lose playing time to Andrew Knapp if he fails to get his bat going soon. The Phillies also have top catching prospect Jorge Alfaro at Triple-A, and he could be an option to come to the majors later this year.