The Gunners made a valiant effort, beating Monaco 2-0 on the night on Tuesday, but had left themselves with too much to do after a poor performance in the home leg
Arsenal defender Per Mertesacker accepts that Monaco deserved their qualification for the Champions League quarter-finals after they survived a major scare to advance on away goals.
Monaco triumphed 3-1 in the first leg at the Emirates Stadium in February, leaving the Gunners with a mountain to climb in Tuesday's return fixture at Stade Louis II.
Arsene Wenger's side almost completed a remarkable revival, as goals from Olivier Giroud and Aaron Ramsey sealed a 2-0 win on the night, but it was ultimately not enough due to the French team's away goals and Mertesacker was left to rue a poor first-leg display.
"I think the best team went through so they deserve it because they played much better in the first leg," he told ITV.
"We had to come back from a massive deficit. We played well today but it wasn't enough.
"That's the truth [Arsenal played a poor first leg] but you never know so you come here and try absolutely everything and, when you look at the game, we could have scored more than two.
"We don't look back at the first game - that was already over. We did our best but it wasn't enough.
"They deserve it. That's absolutely fine because away from home they played much better but we responded well today. We have to admit that our regrets go to the first game.
"You have one bad game in the Champions League and you are out. Even against a team that was underestimated by the public but they deserved it."
