Velasquez left Wednesday's game with what the Phillies are calling "right biceps tightness," the Chicago Sun-Times' Gordon Wittenmyer reports.
He left after just two pitches, which is often a telltale sign of a significant injury. While the team is only classifying it as biceps tightness, he didn't touch 90 mph with either pitch he threw, so it's fair to expect the worst. The team should release further details about the nature of the injury after tests have been conducted.