LONDON -- Arsene Wenger says Santi Cazorla's injury problems are the worst he has ever seen a player go through, but still hopes the midfielder will return to the pitch soon.

Cazorla has not played for more than a year after needing eight different operations to repair a tendon in his heel and the complications that followed.

The Spain international told Marca this month that doctors told him at one point he may never walk again and that his foot may even need to be amputated, but he is targeting a return in January, having been left out of Arsenal's Premier League squad for the first half of the season.

Wenger, who has been in management for three decades, said he has never seen anything like it.

"It is the worst injury I have known, starting with a little pain in the Achilles and it has gone from worse to worse," Wenger told a news conference. "I know how much Santi Cazorla loves to play football and loves to be out there every day and I feel really sorry for what happened to him because it is unbelievable."

Cazorla has been posting regular updates on social media with him working out in the gym as he tries to complete his comeback.

Wenger said he also remains hopeful about a January return for the midfielder, but did not want to set any specific timeline.

Santi Cazorla has been sidelined for more than a year. David Price/Arsenal FC via Getty Images

"Last time I saw him was one month ago. He came here, and I told him to prepare as well as he can," Wenger said. "He has competent medical people around him and he tries to practise. I have not spoken to him recently but I hope he comes back. I left him out of the squad, hoping he would be available in January. That was my target at the start."

Cazorla was handed a one-year contract extension earlier this year despite the injury problems, but his deal expires next summer and there seems to be a real chance he may never play for Arsenal again, though Wenger did not want to contemplate that notion.

"Let's not talk about that, but I hope you are wrong," Wenger said.

The Arsenal boss also addressed Jack Wilshere's situation after being left out of the England squad, with Gareth Southgate citing his lack of Premier League starts as a reason.

But Wenger said Wilshere is "very close" to starting in the league, and that he only has to "keep fit and work hard" to get into the England squad as well.

"At the moment he is on plan and slowly I think he will get into the [mind] of Southgate again," Wenger said. "His creative aspects of his game, if he keeps fit, will be a big asset for him."

Meanwhile, Wenger also said in his news conference that his Arsenal players will have "no fear" against Tottenham on Saturday and scoffed at the notion that they are underdogs in the North London derby.