Arsene Wenger expects Alexis Sanchez to be "very quickly back to his best" for Arsenal despite the uncertainty which surrounded the Chilean star in the final days of the summer transfer window.

It was reported that Arsenal agreed a fee with Manchester City for Sanchez to leave, but that the deal collapsed because the Gunners were unable to complete the signing of Monaco winger Thomas Lemar in time.

Sanchez cut a forlorn figure in the 4-0 defeat to Liverpool prior to the international break, over which he endured more misery with Chile in the World Cup qualifiers. But Wenger has no doubts about the character of his star player.

"I have no doubt about Alexis' mind and mentality, that people question," the Frenchman said. "He needs to come back to full fitness, which he was not (at) against Liverpool. It was his first game, and he has suffered a negative experience with Chile.

"But he is strong mentally and hopefully he will be back very quickly to his best."

Wenger moved on to giving his backing to closing the transfer window before the season starts. Premier League clubs are expected to discuss bringing the deadline forward at a meeting on Thursday.

"It is important that we change that and close all that stuff before the championship starts," he said. "You can see in the games even in the players' minds they have no clarity - are they in, are they out? - and are they being tapped up by people in the game who want to get them out?

"It is not a way to work and it is uncomfortable. It is time to kick that out before the season starts."

Reporting by Press Association