Arsenal defender Hector Bellerin will miss the rest of the season after rupturing the anterior cruciate ligament (ACL) in his left knee against Chelsea, the club have confirmed.

The Spain right-back appeared to twist his knee before falling to the Emirates Stadium turf and departed on a stretcher after 72 minutes on Saturday.

Bellerin was making his first start since suffering a calf strain in December, and head coach Unai Emery accepted after the match things were "not positive" for his defender.

Arsenal confirmed Emery's fears on Tuesday, revealing Bellerin is expected to be out for between six and nine months and will therefore not feature again this term.

"Further to the injury sustained during our match against Chelsea on Saturday, we can confirm that Hector has ruptured the anterior cruciate ligament of his left knee," the club said in a statement on Tuesday.

"Hector will undergo surgery to repair this in the coming days. The rehabilitation process is expected to take between six to nine months and therefore rules Hector out of action for the remainder of this season.

"Everyone at the club will now be working as hard as we can to ensure Hector is back on the pitch as soon as possible next season."

Bellerin has made 19 appearances in the Premier League this season, 18 of which have come as starts.

There was a more positive update regarding Henrikh Mkhitaryan, with the Armenia international expected to resume full training this week after missing the last month with a fractured metatarsal.

Arsenal host Manchester United in the fourth round of the FA Cup on Friday.