In light of Ricardo Carvalho's departure to Real Madrid, Alex started the 2010–11 season as first choice centre back for Chelsea, alongside John Terry. On 3 October 2010, he scored a 25-yard freekick in a 2–0 victory over Arsenal at Stamford Bridge. On 5 October, he was ruled out for up to three weeks after picking up a thigh injury in the final stages of Sunday's 2–0 win over Arsenal, and subsequently withdrew from the Brazil squad for the friendly matches against Iran, and Ukraine. Alex made his return for Chelsea where he made his return on 30 October 2010 and played 90 minutes against Blackburn Rovers in a 2–1 win. On 1 December 2010, Alex suffered a knee injury and was out of action about three months. While rehabilitation on his injury, Manager Carlo Ancelotti would consider signing a new defender if Alex fails to recover from knee surgery before the end of January but Alex failed to do so and Chelsea went on to sign David Luiz from Benfica. By mid March 2011, Alex made his return to training with the first-team squad.