Manchester United striker Zlatan Ibrahimovic has admitted he is not thinking about his future beyond this season and revealed it was "much more than a knee injury" that kept him on the sidelines for close to seven months.

The Swedish striker suffered a double knee ligament damage against Anderlecht in the last season's Europa League clash in April. He underwent surgery in May and United released after his contract expired in the summer, only to sign a one-year deal in August.

Ibrahimovic returned to action after a lengthy layoff in the Red Devils' 4-1 league victory over Newcastle United on 18 November. The former Barcelona and Paris Saint-Germain striker's current deal will run down after the end of the 2017/18 season.

He is delighted to have returned to the pitch and refused to discuss his future plans beyond the ongoing campaign.

"At the moment I am just thankful I can run and push it and play football again. I don't know what the future brings but what happens, happens," Ibrahimovic explained, as reported by the Manchester Evening News.

"I am at the age where I can choose what I want to do. I don't sign five or 10 year deals, I am just happy to be back playing and doing what I am good at.

"It's fantastic to be playing. Jose said, 'Do whatever you want, I trust in you and you know what you have to do,' so I was not worried.

"The contract is all paperwork and I do the physical work. Even if I had a contract or not I needed to train, that's up to the other people.

"I knew I would stay because I wanted to stay. The numbers have never been an issue. I could've signed a deal after two months, but didn't because I am honest with myself. I want to stay because I can perform."

Ibrahimovic or United decided against disclosing the full extent of the striker's injury. He stressed that "working hard" was the secret behind his recovery, which saw him return to the pitch in less than seven months.

"If people knew the real injury, they would be in shock that I was even playing. It was more than the ACL - but I will keep it personal. That's why I choose not to talk of it," the Swede stressed.

"In my recovery I have not rushed anything, I have been out for six and half months. I have been following protocol and my schedule day by day. The only secret has been working hard. Those close to me know what I have been doing – I was working five, six hours a day.

"When it happened I said giving up was not an option. My only focus was on coming back and coming back better. I know it's my head playing, not my knee, my knee has to follow.

"With my experience and career I know what I have to do, but I feel good, I have to be honest. Today I am very proud of the moment, and for everyone around me because I wouldn't have done it alone.

"Thanks to the supporters for keeping me motivated, the coach who's trusted me, the club that believes in me and my family obviously. They have all been key people."