Returning to the tennis world has given Kyle Edmund that sort of weird feeling you get when you've not been somewhere for a while.

Edmund, 27, was away from the ATP Tour for almost two years because of a serious knee injury that left him wondering if he would ever return.

Three operations later, and after hours of rehab and soul-searching, the 2018 Australian Open semi-finalist is gearing up for his Grand Slam singles comeback when the US Open starts on Monday.

"It does feel a little bit like I'm starting my career all over again," said Edmund, who plays Norwegian fifth seed Casper Ruud about 18:00 BST after entering the main draw thanks to a protected injury ranking.

"The first few weeks when I played tournaments, it felt strange to be around the venues and just doing the tournament thing again.

"Like, the little things of waking up on match days, getting on the bus, practising, eating, - the routine. All those that I've done all my career and then I hadn't; it took a bit of getting used to again.

"It has been a positive, of course, and it is nice to be here again. When you're away from it so long you realise what you did have and then what you didn't."

What Edmund did have a few years ago was a ranking inside the world's top 20 and the status of being Britain's leading men's player.

The memorable run to the Melbourne semi-finals, including victory over then world number three Grigor Dimitrov before defeat by eventual runner-up Marin Cilic, catapulted him up the rankings and pushed the reserved Yorkshireman into a limelight he has never seemed entirely comfortable with.

The plan, clearly, was not to disappear from public view for a large chunk of what are often a player's peak years.

Despite the anxiety about whether his body would allow him to return, and the drying up of regular income, Edmund has eventually been able to be reflective.

"I'd say from being out I've learned things about myself. And I've never been in that position before. You learn things about yourself, how you react in certain situations," he said.

"The feelings I had of being upset and frustrated, being down and the worrying, I never felt that on court.

"So I've sort of said to myself when I'm in a match I'll never feel that bad or that angry or frustrated. It feels like because of the battles you have had then, you won't ever feel as bad on the court."

'Playing Ruud is tough but I won't give myself a hard time'

Edmund had been feeling pain in his left knee for several years, with a scan in 2018 revealing fluid behind the bone.

After playing through it and resisting surgery, he decided he needed to go under the knife and had a first operation in November 2020.

Two further surgeries were needed to "clean up" the knee, one in March last year which ruled him out of the entire 2021 season, and another in May when he started to feel discomfort on the practice court.

There was a surprise return to the court in July when he played in the Wimbledon mixed doubles, alongside fellow Briton Olivia Nicholls, before going solo again in a Challenger event in Winnipeg.

Edmund returned to the main ATP Tour in Washington and lost in the second round to Dan Evans, who said it was "not easy" to see his British Davis Cup team-mate go through such a tough experience.

"I know it was difficult for him but I think when you come out of the other side there are positives," mused Evans. "He's back playing on the tour and if he can stay fit this is his level."

Edmund says his knee has "held up pretty well" since he returned to competitive action and that the early stages of his comeback have been "overall positive", while acknowledging he needs to continue being patient with - hopefully - plenty of years ahead of him to recapture his previous level.

"It's been up and down - some weeks felt really good, some weeks not so good. But I've been able to play the matches," he said.

"There's not been too much where I've had to stop but I've just had to manage it in terms of my load. I think that's sort of expected after such a long time out.

"Playing Casper will be tough but there will be a lot of positives that I can hopefully take away from it. I can learn what my true level is because he is at the top of the game right now.

"Right now it is so early coming back it is important that I don't give myself a hard time getting wrapped up in it all, but seeing it for what it is and the strides that I have made to get back."