The Roma midfielder suffered a a muscle strain in training on Tuesday and is likely to miss two or three weeks of action.
"Bradley has suffered a first- to second-degree muscle strain in his right thigh," Roma press officer Catia Augelli told MLSsoccer.com. "He has already begun treatment, and will be monitored and reassessed over the next few days. I think he will be missed for about two or three weeks."
Bradley was off to a flying start with Roma having notched a match-tying assist in his first competitive match for the club over the weekend.
The midfielder has also been a mainstay in the middle of the pitch for the USA, though he was one of the star players not involved in the USA's win against Mexico in Azteca earlier in August.
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