I've heard people (all claiming to be "insiders") on various message boards claiming everything from bruised shoulder to broken collarbone. Not in practice today:
<blockquote class="twitter-tweet"><p><a href="https://twitter.com/search?q=%23USC&src=hash">#USC</a> star WR Marqise Lee who left practice FRI w an apparent shoulder INJ, will NOT practice today, a source just told me.</p>— Bruce Feldman (@BFeldmanCBS) <a href="
">August 10, 2013</a></blockquote>
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But, let's be fair. If there's one guy on that team that could recite the famous Allan Iverson "Practice" speech, it's Lee. No point in exposing your team's MVP to further damage before a single game is played. Apparently, though, they only have five scholarship WR's. Ouch. One injury, and they're digging into the practice squad for players.