GENOA, Italy (AP) -- AC Milan warmed up for its second-leg match at Barcelona with a 2-0 win at Genoa on Friday - but lost two key players to injury just four days before the Champions League match in Spain.
Forward Giampaolo Pazzini was already limping when he scored in the 22nd minute and defender Philippe Mexes also exited at halftime with an apparent injury before Mario Balotelli doubled Milan's lead in the 60th.
Balotelli replaced Pazzini two minutes after Milan's first goal but he can't play in the Champions League because he's cup tied after transferring from Manchester City in January.
Milan finished the match with 10 men after midfielder Kevin Constant picked up a second yellow card for protesting in the 65th.
Still, Milan extended its unbeaten streak to 11 matches and moved within two points of second-place Napoli, which visits Chievo Verona on Sunday.
Also Sunday, Serie A leader Juventus hosts Catania.
"We made a nice little step forward in the table,'' Milan manager Massimiliano Allegri said. "If Napoli permits us, we'll aim for more than third place.''
On Tuesday, Milan takes a 2-0 lead from the first leg to face Lionel Messi and Barcelona again.
Allegri said Pazzini was bruised below the knee, while Mexes was apparently removed for more precautionary reasons.
"His and Mexes' conditions will be evaluated over the next few days,'' Allegri said.
Under intermittent rain at the Luigi Ferraris stadium, Milan controlled at the start but Pazzini appeared to hurt his left leg when he was tackled from behind by Daniele Portanova in the 20th.
However before Milan had time to replace him, Pazzini found himself with the ball at the edge of the area and banged in a shot off the underside of the crossbar.
Balotelli, playing for the first time since getting bruised in the Milan derby two weeks ago, appeared nervous when he came on and was immediately shown a yellow card for pushing down a defender.
Balotelli also received a knock on the left leg he bruised in the derby shortly after coming on.
Genoa then argued for penalties on three different occasions, two for apparent hand balls and one for a push from Milan forward M'Baye Niang, but the referee ordered to play on.
Four minutes into the second half Genoa came closest to the target when Cesare Bovo hit the crossbar with a long, curling free kick.
After Milan midfielder Mathieu Flamini failed to take advantage of two chances, getting yellow carded for diving on the first occasion, Balotelli scored with a sharply angled shot from the edge of the box after being set up by Cristian Zapata.
It was Balotelli's fifth goal in five matches since joining Milan.
Milan didn't have long to celebrate, though, as Constant was sent off five minutes later, prompting Allegri to take off top scorer Stephan El Shaarawy in favor of an extra defender, Ignazio Abate.
El Shaarawy, who has scored 16 goals this season, rarely threatened against his former club.
"After the sending-off we suffered and had to run a lot more,'' Allegri said. "That shouldn't happen at a calm moment of the match like that.''