Sanchez was heavily linked with a transfer away from The Emirates during the summer transfer window after he entered into the final 12 months of his contract at the north London club.
Manchester City were thought to be keen on signing Sanchez before the transfer window closed, but Arsenal refused to sell their talisman and instead kept hold of the 28-year-old.
Sanchez could make his first appearance of the season for the Gunners in the Europa League when they host Cologne at The Emirates on Thursday night.
And despite all of the uncertainty about Sanchez’s future, Bellerin insists that the Chile international remains totally focused on affairs at Arsenal.
Bellerin told the IBTimes: “Alexis is 100 per cent focused on Arsenal.
“He didn’t start [against Bournemouth] after returning from international duty.
“But when he came on he has proved that he is 100 per cent and is going to be in every game.”
Arsenal return to Premier League action on Sunday afternoon when they travel to Stamford Bridge to take on Chelsea.
The Gunners have gotten the better of the Blues in their most recent two outings in both the FA Cup final and Community Shield.
However, Chelsea won 3-1 when the two sides last met back at Stamford Bridge last season in the Premier League.
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