Aaron Ramsey believes Arsenal paid the ultimate price for the red card shown to Gabriel in their Premier League meeting with Chelsea on Saturday.
The game at Stamford Bridge was level approaching half-time, but an altercation between Chelsea striker Diego Costa and the Brazilian centre-back resulted in the latter's dismissal as he retaliated to his opponent's provactions with a kick.
In the second half the hosts took the lead as Kurt Zouma headed home from a Cesc Fabregas free-kick, before Eden Hazard wrapped up a 2-0 win with a stoppage-time strike after Santi Cazorla had also been given his marching orders for picking up two yellow cards.
Ramsey felt that, up to the first sending off, Arsenal had been performing well and could have turned the home fans against their side, who came into the game off the back of two consecutive top-flight defeats, had the numbers remained level.
"We felt quite comfortable out there," Ramsey told Arsenal.com. "They haven't had the best of runs of late and the more the game went on, the more the crowd would have started to turn and moan a bit.
"That set-piece has cost us but we tried our best out there and we paid the price from the sending off in the end."
The result consigned Arsenal to a second consecutive defeat after they went down 2-1 to Dinamo Zagreb in the Champions League in midweek.
And the Welshman added that he is keen for them to bounce back as quickly as possible.
"We're always going to create opportunities but we're just disappointed because we had a bad result in midweek in the Champions League," Ramsey added.
"We wanted to get back to winning ways and have a positive game. We were doing that up until the sending off.
"I'm sure he'll learn from that and we have to move on and put things right on Wednesday [against Tottenham].
"It's not good enough for a club like Arsenal to lose two games in a row."
