Arsenal manager Arsene Wenger has described the latest injury setback suffered by Santi Cazorla as "disastrous".
On Wednesday, the Spain international confirmed he has had to undergo another operation to a tendon in his right ankle and expects his return to be delayed.
The midfielder has not played since a 6-0 win over Ludogorets last October and revealed in a recent interview with Marca that a succession of operations and subsequent infections in his right ankle almost led to him needing to have his foot amputated.
Wenger still hopes the 32-year-old can return to the pitch at the beginning of 2018 but admits it is tough to see Cazorla's problems continue.
"That, for me, is the disastrous, sad news of the day," he told a news conference. "I feel really sorry for Santi; he is a guy I admire and who we all love here.
"He comes into training every day with a smile because he loves the game so much.
"For him not to be available for us is a big blow. For him, as well, it is something that is difficult to take.
"I've been informed medically but I have not read any report. I hope he will be alright and he will be back with us in January. That was planned originally.
"I don’t know whether the surgery will put it back or not. I have to speak to the doctor."
Arsenal, who thrashed Huddersfield Town 5-0 on Wednesday, host Manchester United in their next Premier League match on Saturday.