Matmour quickly made an impact at the club when he scored on his debut, in a 3–2 win over Greuther Fürth in the opening game of the season. Three weeks later on 7 August 2011, Matmour set up two goals for Alexander Meier, who scored twice, in a 3–0 win against Eintracht Braunschweig. Since making his debut for Eintracht Frankfurt, he quickly established himself in the starting eleven for the side, playing in the right–midfield. By the end of 2011, Matmour scored two more goals, coming against FC Ingolstadt 04 and Alemannia Aachen, adding three goals to his tally this season so far. Matmour then scored a hat–trick on 18 February 2012, as well as, setting up one of the club’s goals, in a 6–1 win over FSV Frankfurt. After suffering an injury in early–March, Matmour spent the rest of the season in the first team, coming on as a substitute in a number of matches. Despite this, the club was promoted to Bundesliga after he played 14 minutes as a substitute to help Eintracht Frankfurt beat Alemannia Aachen 3–0 on 23 April 2012. At the end of the 2011–12 season, Matmour went on to make 30 appearances and scoring 6 times in all competitions.