For instance, Ross Zafonte, a traumatic-brain-injury and rehabilitation expert at Harvard-affiliated Massachusetts General Hospital, said he was treating two patients who played the same position for a similar time in the league.

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Farrell said right fielder Shane Victorino, on the disabled list since May 21 because of a strained left hamstring, likely will have a two-day injury rehabilitation assignment and be activated for Wednesday's game against Texas.

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Red Sox RF Shane Victorino, on the DL since May 21 because of a strained left hamstring, likely will have a two-day injury rehabilitation assignment and be activated for Wednesday's game against Texas. 3B Will Middlebrooks, on the DL since May 24 with a lower back strain, is on track to be activated Thursday.

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He underwent brain surgery and spent months in a brain injury rehabilitation unit.

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Highly-rated open-side flanker Lewis suffered a similar injury in May and is six weeks into his own rehabilitation programme with the region expecting him to be fit again by November.

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Defender David van Zanten has already been signed from St Mirren and tricky midfielder Fabian Yantorno has been undergoing rehabilitation from injury at Hibs since his release from Gretna.

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So began the long process of rehabilitation, surgery, another stint of rehab and dealing with another injury, a bone bruise.

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He holds academic appointments with the Department of Rehabilitation Medicine at Emory University School of Medicine and the Emory Center for Injury Control.

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"If he feels good, I don't see this injury being career-ending, " said Dr. Robert Gotlin, the director of orthopedic and sports rehabilitation at New York City's Beth Israel Medical Center.

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