Jorge Martinez's injury hit campaign continues after he picked up another problem in training on Thursday.
The Uruguayan, signed for a massive €12m from Catania in the summer, limped out of today's session with a muscle problem in his left thigh.
The South American will undergo medical tests on Friday in an effort to assess how serious the issue is.
Martinez, a wide attacker who has struggled to adapt to Gigi Del Neri's 4-4-2, has only played in 12 League games so far this term for a total of 486 minutes.
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