Alexandre Lacazette apologised for his red card in Arsenal's Europa League defeat to BATE, a result team-mate Petr Cech acknowledged has made life tough in their quest to reach the last 16.
The Gunners endured a miserable Europa League first-leg encounter in Belarus, losing to Stanislav Dragun's first-half header as Lacazette was dismissed in the closing minutes.
The forward, who elbowed defender Aleksandar Filipovic late on, posted on Twitter: "Letting the team down like that is the worst feeling. I should have stayed calm but it's not always easy. Sorry.
"There are still 90 minutes to play and I believe that my team-mates will make it to the next round."
And goalkeeper Cech was frustrated to see Arsenal struggle in attack, albeit Lacazette saw a goal rightly ruled out for offside.
The Premier League side must now overturn the 1-0 deficit back at Emirates Stadium next week.
"We didn't take our chances," Cech told the club's official website. "I think that, in the first half, we played well and created enough chances to go ahead in the game.
"But, unfortunately, we didn't take our chances and we conceded in the last minute of the half, which obviously gives them a lot of confidence and belief.
"In the second half, they were waiting for the counter-attack and we were trying to find our way to score the goal and we scored one, but it was ruled as offside.
"We got the result we didn't want. We want to score goals and we want to win and we want to put ourselves in a good position for the second leg, but we've made it more difficult for ourselves."
