Coach Gus Bradley says Shorts felt tightness in his left hamstring while running at the beginning of practice, so team trainers shut him down as a precaution.
Bradley hopes Shorts will be able to play Sunday at Philadelphia. But it's no certainty, especially given Shorts' history.
The fourth-year receiver missed more than three weeks of training camp because of a strained right hamstring and sat out most of organized team activities with a calf injury. He missed six games with a hamstring injury in 2011, two games because of a concussion in 2012 and three games in 2013 with a groin injury that slowed him all season.
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