Former world number one Roger Federer said he has no real expectations for his comeback event at the Qatar Open.

Federer has not played competitively since his semi-final exit at the 2020 Australian Open – the 20-time grand slam champion having undergone knee surgery last year.

The 39-year-old Swiss superstar opted not to travel to Melbourne for this year's Australian Open, but he is set to make his comeback in Doha.

Federer, who holds the record for most Qatar Open titles with three – will start his campaign against either Jeremy Chardy or Daniel Evans at the ATP 250 tournament.

"It's been a long year in some ways, especially rehabbing, being on crutches once and then for a second time, and finally I'm back on a tennis court again, working out, playing sets, playing points," Federer said.

"It's a true pleasure, it's a privilege actually after all this time. I didn't expect it to go as long as it did, we are where we are, I'm so excited to be back on a match court, you know, in a few days here.

"I'm really curious to find out how it's going to go, obviously there's an amazing amount of questions marks surrounding my comeback for me personally.

"I don't know what to expect, I know that expectations from myself are extremely low, and I'm just very happy that I'm playing a tournament again, regardless of the outcome of this event."

On whether he had doubts over returning, Federer added: "You always do have doubts, you know, when you have surgery, there are always days when you feel better and worse. But I think overall I am a very positive person, I have a great team around myself, my family, I am also very distracted, and you know, the idea was to be fully fit again, one day. For life or for tennis.

"So equally important to me, actually life is a little bit more important to me, I wanna go skiing and play basketball, I wanna go playing ice hockey, play tennis in the future, with my children or exhibition matches, you name it, so it's definitely worth it to go through all that pain you know. But the goal was, this is not I'm going to go out, I'm not happy with my knee, we're going to fix it, and then I'm going to come back.

"For me there was no other story to it, and rehab wasn't as hard as maybe people make it seem, even though people around me are very impressed how I go about it, but for me it's only but normal to be really, really professional about it."