Koscielny started every game in the first month of the season, excluding a 0–0 draw with rivals Liverpool at Emirates Stadium, due to an injury. Koscielny played a vital part as Arsenal won 5 games out of six in October to go second in the Premier League, with Koscielny scoring in successive Premier League wins against Everton and Swansea. With manager Arsene Wenger opting to play Gabriel Paulista ahead of vice-captain Per Mertesacker, Koscielny began appearing as captain in February, due to injuries to other captains Santi Cazorla & Mikel Arteta. This ended after a 3–2 defeat to Manchester United, when Koscielny missed four games through injury, including a North London derby at White Hart Lane. He returned in a 3–1 away defeat to Barcelona in the Champions League, as Arsenal exited the competition at the round of 16 for the sixth season running. Koscielny scored his fourth of the season in a 3–3 draw with West Ham.