A's P Parker leaves with injury

Oakland Athletics pitcher Jarrod Parker fell to the ground in pain after delivering a pitch in the fourth inning of Saturday's game against the St. Louis Cardinals and exited with an apparent hamstring injury.

Parker stopped short on his follow-through on an offering to Allen Craig with two outs in the fourth and doubled over in obvious pain while grabbing the back of his right leg, just above the knee.

The right-hander stayed on the ground and tried working out the kinks, but after throwing several warm up pitches, he walked off the field under his own power as Jesse Chavez relieved him from the bullpen.

Parker gave up two hits before leaving -- one when Craig doubled the injury- induced pitch off the wall in left-center. He left with the game in a scoreless tie, keeping his streak of four consecutive winning decisions in tact.