Granit Xhaka's dismissal in Arsenal's 3-2 victory over Swansea City on Saturday was only worthy of a "dark yellow" card and not a red, according to Arsene Wenger.
Switzerland international Xhaka was sent-off in the 70th minute of the match at the Emirates Stadium for lunging in on Modou Barrow from behind, clipping the back of the Swansea winger's legs.
It is the fourth time since the start of last season that the midfielder has been given his marching orders, more than any other player in the top five European leagues.
Wenger does not believe Xhaka plays with intentional malice and felt a seemingly over-exaggerated reaction from Barrow played a part in referee Jonathan Moss reaching his decision.
"It looked harsh to me - a dark yellow but the referee went for a bright red," said the Frenchman in his post-match news conference.
"He's not a dirty player at all but I think Barrow made a lot of it as well. You have to respect the decision and he has to learn from it."
Theo Walcott's first-half double was followed by an exceptional strike from Gylfi Sigurdsson before half-time.
Mesut Ozil volleyed home Arsenal's third before Borja Baston pulled one back for Swansea, with the Gunners holding onto the win after being reduced to 10 men.
Wenger was pleased with the character his team showed to see out the victory, though he was disappointed to see their two-goal lead slip in the first half.
"What looked to be a comfortable afternoon finished in an uncomfortable way but we just got over the line," he added.
"I think we played some fantastic football but at 2-0 we lost our focus. We could have scored the fourth goal and we could have conceded, but we played with spirit and got there in the end.
"I feel what makes the difference is everyone that comes on is focused and that helps a lot."