Alexandre Lacazette was the star for Arsenal, scoring within 21 seconds of coming on as a second half substitution, as the side beat Brighton in the Premier League on Tuesday.
On the field, Arsenal eased fears they could be dragged into a relegation battle with a 3-1 win over Chelsea on Saturday and can now look up the table with hope thanks to consecutive league wins for the first time since the opening two games of the season.
Pierre-Emerick Aubameyang returned from injury in the place of Alexandre Lacazette in the only change made by Arteta.
But Lacazette came off the bench to make an instant impact and win the game with a fine near-post finish from Bukayo Saka’s pass.
Victory moves the Gunners up to 13th, within seven points of the top four.
West Brom are next up for Arsenal at the weekend and the Baggies confidence after a shock 1-1 draw at Liverpool on Sunday quickly evaporated in a 5-0 hammering by Leeds.