In this case, the random AAA pitcher was Jeremy Hefner, who was briefly on the Pirates' 40-man roster last winter. Hefner pitched seven shutout innings, allowing three hits and no runs while striking out seven and walking one.
Locke, meanwhile, struck out five batters and walked one over three innings, but ran into problems in both the third and fourth. Ruben Tejada hit a one-out single in the third and took second on his complementary stolen base; he then came home to score on a line-drive single by Daniel Murphy, thanks in part to Andrew McCutchen, who misplayed the ball. David Wright then singled. Murphy scored and Wright moved to second after a throwing error by Pedro Alvarez. Then Scott Hairston doubled down the line, knocking in Wright, and, after a flyball out by Ike Davis, Kelly Shoppach singled home a fourth run. Locke also allowed three of the first four batters he faced in the fourth to score, before being replaced by Chris Leroux.
An ugly fourth inning might have been longer if Starling Marte hadn't gunned down Murphy at home to end the inning, but by then, the damage was already done. And ... well, yeah, that was about it. It was just one of those games where it seems like the Pirates offense decides to take the day off for some reason. In this case, they managed just the three hits overall. I'm sure it'll be a day Hefner will remember forever, because most teams don't get three-hit by bad pitchers like the Pirates do.