Smith Rowe scored the only goal of the London derby in the 16th minute from just yards out.
Chelsea midfielder Jorginho thought that he was passing the ball back to his goalkeeper Kepa Arrizabalaga, but it was rolling into an own open goal.
Kepa scrambled the ball away, only for it to reach Arsenal striker Pierre-Emerick Aubameyang, who teed up his teammate and attacking midfielder Smith Rowe to slot in.
It was the 20-year-old’s second goal in the Premier League following his strike in the 3-1 win against West Bromwich Albion at the Emirates Stadium in North London last weekend.
The English youngster has made 16 starts and two substitute appearances in the Premier League this season, scoring two goals and providing four assists in the process.
Smith Rowe has also made eight starts and three substitute appearances in the Europa League for Arsenal this campaign, scoring one goal and providing three assists in the process.
Arteta told Arsenal’s official website about Smith Rowe: “Yes, he did it. Pressing really high, and the commitment that those players put in to try to be as high as possible and try to create difficulties, he got rewarded.”