Sagna scored his first goal at the Emirates Stadium for Arsenal against Celtic, a game in which Arsenal went on to win 3–2 and win the Emirates Cup for the second consecutive year.
He made his 100th league start for Arsenal on 3 October 2010, a 2–0 defeat against Chelsea at Stamford Bridge.
On 14 November, he scored only his second ever official goal for Arsenal in a 2–1 away victory against Everton at Goodison Park, with a powerful shot from the near post.
On 8 December 2010, Sagna picked up his first red card in his Arsenal career in a 3–1 home victory against Serbian club Partizan in Arsenal's final Champions League group game of the season.

On 1 January 2011, in a match with Birmingham City, he was involved in an incident where Lee Bowyer stamped on him after Sagna had gone in for a tackle.
Bowyer was banned by the FA for three games for the stamp.
On 5 January, Sagna picked up his second red card of the season after he and Manchester City fullback Pablo Zabaleta headbutted each other in the final moments of Arsenal's 0–0 draw with City at Emirates Stadium.
On 19 January, Sagna scored his second goal of the season with Arsenal's second goal in their 3–1 victory over Leeds United at Elland Road in a third round replay.
This was Sagna's career best for goal-scoring, his previous best coming in the 2007–08 season where scored only once.
Sagna was included in the PFA Team of the Year for his performance in the 2010–11 season.
Sagna scored his first goal at the Emirates Stadium for Arsenal against Celtic, a game in which Arsenal went on to win 3–2 and win the Emirates Cup for the second consecutive year. He made his 100th league start for Arsenal on 3 October 2010, a 2–0 defeat against Chelsea at Stamford Bridge. On 14 November, he scored only his second ever official goal for Arsenal in a 2–1 away victory against Everton at Goodison Park, with a powerful shot from the near post. On 8 December 2010, Sagna picked up his first red card in his Arsenal career in a 3–1 home victory against Serbian club Partizan in Arsenal's final Champions League group game of the season.
On 1 January 2011, in a match with Birmingham City, he was involved in an incident where Lee Bowyer stamped on him after Sagna had gone in for a tackle. Bowyer was banned by the FA for three games for the stamp. On 5 January, Sagna picked up his second red card of the season after he and Manchester City fullback Pablo Zabaleta headbutted each other in the final moments of Arsenal's 0–0 draw with City at Emirates Stadium. On 19 January, Sagna scored his second goal of the season with Arsenal's second goal in their 3–1 victory over Leeds United at Elland Road in a third round replay. This was Sagna's career best for goal-scoring, his previous best coming in the 2007–08 season where scored only once. Sagna was included in the PFA Team of the Year for his performance in the 2010–11 season.
Bacary Sagna