Marek Hamsik is a key figure for Napoli but will need to recover from a foot injury ahead of schedule if he is to face Arsenal.
Having come on as a substitute due to worries about his fitness, Hamsik seemed to catch his studs in the turf and had to be taken off again.
As he left the pitch, Hamsik reportedly apologised to coach Rafa Benitez, who had warned him not to play if not fully fit.
Hamsik is unlikely to feature against Udinese on Saturday, but he is making every effort to be ready for Napoli's crucial final Champions League group game against Arsenal.
According to Sportmediaset, the 26-year-old is still feeling pain in his foot but is continuing to train with the use of special insoles in his boots.
Napoli must beat Arsenal to stand a chance to progressing in the competition, while the Gunners must just avoid a 3-0 reverse.
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