Dominguez was called up by the Phillies on Monday.
The 23-year-old transitioned to the bullpen this season and took to it immediately. He struck out 18 batters with a 2.08 ERA in 13 innings for Double-A Reading before tossing 3.2 scoreless innings for Triple-A Lehigh Valley. He had never pitched above High-A before this season, so expectations shouldn't be too high, but relievers can sometimes develop very quickly and he could be one of them. If he continues his dominance at the major-league level he has a chance to stick with the team the rest of the year and work his way into a higher-leverage role. He certainly has the stuff to be an impact reliever, with a fastball that can touch 99 mph and a plus slider that sits in the high 80s. A corresponding move has not yet been announced.