AC Milan thrashed Arsenal 4-0 at home in the first leg of their Champions League final-16 tie on Wednesday.

Former Tottenham man Kevin-Prince Boateng scored a sensational volley and Manchester City outcast Robinho bagged a classy brace before Zltan Ibrahimovic converted a penalty to cap an inspiring performance of the Italian giant.

Arsenal manager Arsene Wenger would almost throw in the towel believing his side's hopes of knocking Milan out of the Champions League are all but gone.

"Statistically it' s too big a deficit," said Wenger when asked whether his men can turn this around in the second leg.

"We'll try of course but the result is massive for them, very difficult to turn and we cannot do worse than tonight. A defeat can happen when you play well but defensively we were poor, we were never in the game and it is a big shock," he said.

Wenger's Milan counterpart Massimiliano Allegri still wasn' t entirely content with the result as he believed his side could have scored more.

"Tonight we had so many chances, especially after going 4-0 up. We could' ve won 6-0 and ought to take our chances when they appear, above all in Europe," he said.

"I hoped to add some more to the result, because we have to take the opportunities. The result is good, but it would' ve been better to score a few more and definitively end the tie. Now we need a goal in London to relax," he added.

Milan had not won any of their previous seven matches against English clubs, knocked out of the Champions League at this stage by Tottenham last season.

However, the Serie A leaders never looked in danger of a repeat, well organised from kick-off as Arsenal struggled to get any sort of foothold.

Boateng fired the Italians ahead with a quarter of an hour gone. The former Portsmouth and Tottenham midfielder collected a chip to the edge of the Arsenal penalty area on his chest, before turning to fire the ball over Wojciech Szczesny and in off the underside of the crossbar.

It was 2-0 in the 38th minute when Ibrahimovic charged down the left channel and crossed for Robinho to nod in from six yards.

Milan extended their lead four minutes after the break when Robinho slammed home what looked to be a tie-clinching third goal.

Milan keeper Christian Abbiati produced a brilliant one-handed save to turn around van Persie's volley after a flick-on by Henry on 65 minutes.

However, any hopes of comeback for the Gunners were ended in the 78th minute when Djourou bundled over Ibrahimovic to concede a somewhat soft penalty, which the big Swede slotted into the bottom right corner, leaving Arsenal a mountain to climb in the return leg at Emirates Stadium on March 6.