Mason Mount was instrumental in Chelsea’s 2-0 win at the San Siro as the Blues moved top of Group E and handed ten-man AC Milan a fourth consecutive Champions League defeat against Premier League opposition.After bouncing back from their 3-0 loss at Chelsea last week with a 2-0 home win over Juventus, AC Milan controlled possession early on in front of a roaring San Siro as they went in search of their sixth home win this season. Chelsea, though, were going to prove a stubborn opponent following their four-match unbeaten run under Graham Potter, and the visitors gradually probed forward.This led to the first chance when Mason Mount got in behind ex-teammate Fikayo Tomori, who pulled the midfielder down as he was through on goal. It was a double punishment for Tomori as he was sent off, and Jorginho sent Ciprian Tătărușanu the wrong way from the subsequent penalty to score from the spot for the Blues for the 21st time.Despite Milan’s numerical inferiority, Olivier Giroud almost stunned his former club with a free header from six yards, but the Frenchman headed high and wide. The scare did little to deter Chelsea, now hunting a fourth consecutive win, and Pierre-Emerick Aubameyang doubled the visitors’ lead by slamming a low strike past Tătărușanu after Mount’s deft through ball.Instinctively, Chelsea pushed on after the break as they looked to put the game to bed. Substitute Conor Gallagher almost made an instant impact, firing wide from a tight angle, before Aubameyang was denied by Tătărușanu’s reaction save. Yet, Milan occasionally displayed the kind of threat that previously led to a nine-match scoring streak at the San Siro, with Sergiño Dest blazing wide from close range after a fluid Rossoneri counterattack.CHAMPIONS LEAGUE: Juve’s debacle in Israel, no Haaland no goals for Man CityThe defeat will be a huge setback for Milan’s hopes of qualifying for the UCL knockout stages. But progress is still in their grasp, although they must produce more positive results against Dinamo Zagreb and Salzburg in their final two group fixtures. In contrast, this was a big result for Chelsea, and the Potter revolution continues as the Blues move top of Group E.UEFA CHAMPIONS LEAGUE – GROUP STAGERound 4Tuesday Maccabi Haifa – Juventus 2-0 (2-0)/Atzili 7, 42/Copenhagen – Man.City 0-0Shakhtar – Real Madrid 1-1 (0-0)/Zubkov 46 – Rudiger 90+4/Dortmund – Sevilla 1-1 (1-1)/Bellingham 35 – Nianzou 18/AC Milan – Chelsea 0-2 (0-2)/Jorginho 21 pen, Aubameyang 34/PSG – Benfica 1-1 (1-0)/Mbappe 40 pen – Joao Mario 62 pen/Celtic – RB Leipzig 0-2 (0-0)/Werner 75, Forsberg 84/Dinamo Zagreb – Salzburg 1-1 (0-1)/Ljubicic 41 – Seiwald 12/Wednesday 19.45: (1.65) Napoli (4.20) Ajax (5.90)19.45: (1.49) Atl.Madrid (4.30) Club Brugge (7.75)22.00: (2.55) Sporting (3.40) Olympique Marseille (3.00)22.00: (8.00) Rangers (5.30) Liverpool (1.43)22.00: (1.58) Tottenham (4.30) Eintr.Frankfurt (6.75)22.00: (2.35) Leverkusen (3.50) Porto (3.25)22.00: (1.48) Barcelona (4.70) Inter (8.00)22.00: (15.0) Plzen (8.50) Bayern (1.18)***odds are subject to change©FlashScore