Avila, 25, entered Tuesday hitting .254/.342/.435 with five homers, 20 RBI and 18 runs. He was an All-Star last season and has been repeatedly called one of the Tigers most valuable players by manager Jim Leyland.
The Tigers entered Tuesday trailing the White Sox by six games, so losing Avila would be a big blow. For now, the Tigers have said he'll be further evaluated Wednesday.
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