The South American is facing an uncertain future at the north London club after failing to agree a new contract with Arsenal despite entering the final 12 months of his current deal.
Naturally, Sanchez has been the subject of transfer speculation over the past few months amid talk of interest from Ligue 1 side Paris Saint-Germain and Serie A champions Juventus.
Worryingly for Arsenal fans, Premier League champions Chelsea have been touted as a potential destination for Sanchez, although a move to Manchester City looks more likely.
Chelsea goalkeeper Courtois backed Arsenal to survive without Sanchez if the Chile international does leave in the summer transfer window.
“Alexis is a guy with a lot of quality. If you see all the games from last season there is a lot of danger coming from him,” Courtois is quoted as saying by Evening Standard.
“He has a very strong shot, he is quick. He has the technique. He is important for them but Arsenal have a lot of players with quality.
“So they will miss him but I think they have a lot of players with that quality to replace him. I think they have bought a good new striker (in Lacazette).
“I’d prefer if he (Sanchez) doesn’t play because he is a good player! But we cannot only look to him.
“For example in the FA Cup Final (Arsenal beat Chelsea 2-1 in May) they missed some defenders and everybody thought they would be bad. But Per Mertesacker played a great game that day.
“So you cannot look to the team as one player or another player. It will be a difficult game regardless but I hope for the same outcome as the friendly last week.”
Sanchez has scored 24 times in 37 games in the Premier League last season to finish as Arsenal’s top goal-scorer.
The Gunners signed Sanchez in a £35m deal from La Liga giants Barcelona in the 2014 summer transfer window ahead of interest from their rivals Liverpool.
Sanchez has won the FA Cup twice since moving to Arsenal.
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