The Spaniard fears he fractured his shin while firing home an 85th-minute penalty to level it at 2-2 and keep Arsene Wenger's dream alive.
Scans taken immediately after the quarter-final first leg proved inconclusive but skipper said: 'I am not good. I fear the worst, which it that I broke something but we will have to wait. I hope I will be able to wear the Arsenal shirt again this season.
Floored: Arsenal players show their concern as injured Cesc Fabregas goes down in a heap
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