On 12 February 2012, Alex made his debut for PSG in a 0–0 draw against Nice, where he made his first start before coming off for Christophe Jallet at half-time. The following week, on 19 February 2012, Alex scored a 30-yard goal from a lay-off free kick, his first goal for PSG, against Montpellier on a free-kick combination with compatriot Nenê, which the result was 2–2. On 8 April 2012, Alex scored the winning goal in the 61st minute in a 2–1 win over Olympique de Marseille. On 6 November 2012, in a Champions League match against Dinamo Zagreb, Alex scored the first goal of the match, a half-volley that evaded the reach of Dinamo goalkeeper Ivan Kelava after 16 minutes.