In the 2011–12 season, Turnbull began to get some more playing time. His first appearance of the 2011–12 season came he played in the League Cup third round against Fulham. The game finished 0–0 after extra time, and Chelsea subsequently beat Fulham 4–3 on penalties to go through to the next round. During normal time, Turnbull saved a penalty from Pajtim Kasami after Alex gave away the penalty (which resulted in a red card for Alex). In the penalty shootout, Turnbull saved two penalties from Mousa Dembélé and Bryan Ruiz. His next appearance in the League Cup was in the last 16 match against Everton. With 58 minutes gone, he conceded a penalty and received a red card. Čech took his place after coming on for Romelu Lukaku and saved the penalty from Leighton Baines. Chelsea went on to beat Everton 2–1 and go through to the next round. A quarter final appearance followed, and was to be his, and Chelsea's, last in the League Cup as they lost 2–0 to Liverpool. During the match, Turnbull saved a penalty from Andy Carroll, given away once again by Alex. With the 2011–12 Premier League season almost over, Turnbull played the final two league games against Liverpool (lost 4–1) and Blackburn (won 2–1) as Čech was rested prior to the Champions League Final, in which Turnbull picked up a medal as an unused substitute. The game against Liverpool was his first league match in two years. His poor clearance led directly to a goal from Jonjo Shelvey.