Roy Keane explains what he should have done after leaving Manchester United

Roy Keane admits he should have retired when he controversially left Manchester United in 2005.

The iconic former United captain needs no introduction for his achievements at Old Trafford and beyond. He made 478 appearances for the club and won everything worth winning during his 12-year stay.

A high-profile bust-up with Sir Alex Ferguson led to his departure. Keane then played ten matches for Celtic before he eventually decided to hang up his boots and pursue a career beyond playing in management and as a TV pundit.

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Keane is a regular on Sky Sports and other broadcasters these days and he was pressed on his decision to sign for Celtic by former United teammate Gary Neville on his The Overlap channel. Things did not go to plan for Keane, 52, when north of the border and he reckons he "embarrassed" himself after leaving United.

Speaking on the popular Stick To Football podcast, Keane said: "I was 34 when I finished, but I should have retired when I left United. I even lost a bit of the love for the game after that.

"I went up to Celtic, but my hip was really at me, painkillers for training... I tore my hamstring two or three times up at Celtic. I was commuting. I still had a year left on my contract and I rang Gordon [Strachan].

"I went to see the hip specialist who said the longer you play on, the worse damage [you will do]. He was talking about when I retire, about quality of life."

Keane added: "I rang Gordon Strachan about what do I do. I had gone up there and kind of embarrassed myself, I wasn't really doing the business. I'd said I'm finished, but losing sleep before I rang him, as soon as I put the