AC Milan will be without Pato for the rest of 2010 after tests confirmed he sustained damage to his left thigh muscle in Wednesday's 3-1 victory at home to US Città di Palermo.

The Brazil striker, who opened the scoring to help the Rossoneri to the Serie A summit, picked up the injury after 65 minutes and was replaced by Filippo Inzaghi – who subsequently suffered a season-ending knee injury a quarter of an hour later. Pato underwent tests on Friday and a Milan statement confirmed "he will need six weeks to resume playing".

The 21-year-old, who has scored six goals in eight Serie A appearances this season, will miss the remaining UEFA Champions League Group G matches away to AJ Auxerre on 23 November and at home to AFC Ajax on 8 December. Massimiliano Allegri's men are second in the section, five points behind leaders Real Madrid FC but one and two ahead of Ajax and Auxerre respectively.