The winger is staring for Bayern Munich tonight in their Champions League round of 16 clash against Liverpool.
Sadio Mane put Liverpool ahead but Gnabry played a huge part in getting Bayern level, with his work leading to Joel Matip’s own goal to make it 1-1.
The ex-Arsenal ace has been key for Bayern this season, with the German international, scoring nine goals in all competitions.
The 23-year-old’s career has turned around since leaving Arsenal in 2016 after struggling to get regular game time.
The Gunners sold Gnabry to Werder Bremen for just £5million – and Arsenal fans can’t believe they let him go.
One fan wrote on Twitter: “We actually sold Gnabry.
Another added: “Til this day, I don’t understand why arsenal sold Serge Gnabry.”
“I just wanna know how Arsenal f****d up so bad with Gnabry,” said a fellow supporter.
Another fan said: “Is the Gnabry in Bayern the same as Arsenal?”
“Gnabry another quality player we let go on a free,” fumed another supporter on Twitter.
Another Arsenal fan said: “As if Gnabry is starting for Bayern at this level ffs.”
Liverpool are currently level with Bayern in Germany tonight.
If the score stays as it is, the Reds will progress into the Champions League quarter-finals.
Liverpool are hoping to join Manchester United, Manchester City, Porto, Ajax, Tottenham and Juventus in the final eight.