The German was widely expected to leave the club back in the summer.

Former Arsenal boss Unai Emery publicly declared last summer that he would be willing to let Mustafi leave the club after the defender’s poor campaign last season.
With Emery now gone, the German had a good run of games under Arteta and he has impressed. Mustafi is back on the good side of Arsenal fans and it looks like his long-term future is at the Emirates.
Asked about staying at Arsenal beyond the end of the season, he said: “Why not? I have always taken things day by day.
“We had a game on Thursday, we have the next important game at the weekend and as long as I am playing for a club — it doesn’t matter which one, I play now for Arsenal and played before for previous ones — I always give everything until the last minute.
“When I decide, or when the club and I decide, it is going to continue, I am happy to continue. If not, then we have to go forward.”

Mustafi has now played 16 games for Arsenal in all competitions. He played the full 90 minutes in each of Arsenal’s last three games and successfully kept three impressive clean sheets.
His partnership with David Luiz has provided a sense of balance to Arsenal and Arteta certainly seems to have full faith in the duo’s ability at the back.
The German’s current deal at Arsenal runs out in the summer of 2021. If he continues his good performances until the end of the season, a new contract could well be on the cards which is something nobody would have predicted about six months ago.

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