Late goals from Cristian Zapata and Sulley Muntari secured a 2-0 win for unconvincing AC Milan over a plucky Celtic side in their Champions League Group H opener on Wenesday.

A raft of injuries to key Milan players including Kaka and captain Riccardo Montolivo forced coach Massimiliano Allegri to reshuffle his squad and gave Neil Lennon's men hopes of causing a major upset at the San Siro.

But after a promising second half from the visitors, in which striker Anthony Stokes hit the woodwork with a curling free kick, Zapata broke the deadlock with a deflected shot on 82 minutes and Muntari poked home a rebound from Mario Balotelli's free kick three minutes later.

Having battled through a tough qualifying campaign Celtic came to Milan brimming with confidence but with 20 defeats in their previous 22 away games in the competition, history was against them.

Indeed it took Celtic until the half hour mark to really settle, by which time depleted Milan had threatened several times.

After just four minutes Balotelli volleyed Valter Birsa's delivery from 12 yards out only for Fraser Forster to block while the 'keeper did well minutes later to stop Birsa as he charged down under pressure from Mikael Lustig.

Lustig was lucky to escape without a caution when he upended Balotelli as both players challenged for the ball in midfield.

Minutes later Celtic were awarded an indirect free kick metres from goal after an infringement by Christian Abbiati but Charlie Mulgrew's shot was blocked by Kevin Constant as Milan packed the goalline.

Milan spurned further chances, with Balotelli's flicked-on header blocked by Forster and unmarked Antonio Nocerino seeing his dipping half-volley from Phillipe Mexes's cross sail just over.

Celtic's only realy chance of the half came on 40 minutes Stokes turned Constant after battling down the left only to drive his shot into the side-netting.

Milan, meanwhile, finished the half as they had started, Balotelli collecting Matri's lay-off and seeing his deflected low drive force Forster to parry while Muntari half-volleyed a poor clearance barely a metre over.

Milan kicked off the second half but it was Celtic who threatened in the early exchanges.

After Kris Commons skewed an early shot wide Lustig flicked on a header from a corner that was cleared by the Milan defence.

The Swede spurned another chance when he sent his delivery from deep on the right flank wide of Abbiati's goal and Celtic edged closer when Samaras sent a 20-metre drive just wide of Abbiati's upright.

Milan set up in Celtic's third of the pitch briefly, with both Zaccardo and Balotelli seeing shots blocked by the defence.

However Celtic upped the pace and after a Balotelli free kick hit the defensive wall the visitors countered to give Scott Brown a solid scoring chance but the skipper's tame shot was collected by Abbiati.

Both sides made changes, with Brazilian midfielder Robinho replacing Constant and Dirk Boerritger coming on for Adam Matthews.

Celtic came agonisingly close when Stokes sent in a delightful free kick from 25 yards which hit the crossbar.

It was a miss that would be felt minutes later when Zapata hit a low drive from 20 yards out and took a deflection off Emilio Izaguirre to leave a beaten Forster rooted to the spot.

Milan grabbed their second five minutes later when Balotelli's powerful free kick was somehow kept out by the 'keeper, but with Muntari pouncing from close range to fire home the rebound.