Having already missed one start, Roy Oswalt is having his next start pushed back so that he can be examined in Houston by Dr. Mike McCann. He will likely have an MRI to determine the severity of the strain, but the fact that he had pain playing catch on flat ground is not a good indication, so a DL possibility is certainly there. He also received a pain-killing injection on Saturday , so it is obviously hurting him a fair amount.
This is presenting like a strain of the Gluteus Medius (hip abductor). He felt the pain originally during his start on June 30, while pushing off the rubber. At push-off, the Gluteus Medius abducts the thigh (pushes the thigh outward against the rubber), and stabilizes the pelvis - preventing it from dropping down on the contralateral (opposite) side.
He has not been terribly effective this season, yielding a whopping HR/FB percentage of 16.4% (career average of 9%), and an increased line drive percentage of 22%, which is up from the past two seasons (16% and 19.9%). Contrary to the popular belief that his velocity has been down, his average fastball this season is 92.5 mph, which is consistent with past seasons (92.7 in ‘07, 92.7 in ‘06, 93.1 in ‘05). One trend I have noticed is that he is using his fastball less and less since 2005, relying more and more on his slider and curveball - especially this year, perhaps due to this nagging hip injury. Thank you to Fangraphs for the data.
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