Mario Balotelli is out of AC Milan's crucial Serie A game against Lazio on Saturday with knee injury picked up in last week's derby.

AssociatedThe draw against Inter was Balotelli's fourth game for Milan and the first in which he did not score

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Milan manager Massimiliano Allegri confirmed to reporters the £19 million striker is "99.9%" certain to not play.

"Balotelli won't play against Lazio, he has internal bruising and isn't available," Allegri told Milan Channel. "He's been out of action for a week and can't play."

Balotello, 22, took a knock to his right knee when he clashed with Inter Milan goalkeeper Samir Handanovic in last Sunday's derby, which finished 1-1.

The injury could not have come at a worse time for Allegri as Lazio are currently sitting in the third Champions League place on 47 points with his Milan side two points behind in fourth.

Balotelli has scored four goals in four games for Milan since signing from Manchester City in January.