Manchester United midfielder Ryan Giggs has admitted he fears the time when he realises he will have to retire.
The Welshman is keen to keep pushing forward irrespective of turning 40 this week.
The United stalwart conceded it will be a specific incident in the future that tells him he must call it a day.
But after 953 appearances for the Old Trafford club, Giggs is still trying to prolong his playing career for as long as possible.
"There will be some incident, something will not be quite right, I'll feel different," he told BBC's Football Focus.
"I'm obviously wary of that because I'm still wanting to do well and wanting to focus on winning games."
Giggs backed manager David Moyes to guide United to retaining their Barclays Premier League title, despite an indifferent star to the new manager's reign.
He said: "Of course we can win it again. We haven't got off to a great start but we've picked up more consistency lately.
"From the experience of the years, you know you just hang in there and hang in there and hopefully something will happen.
"When you're starting out you don't look forward 10 to 15 years, it's a million miles away.
"He (Sir Alex Ferguson) was a massive part of my career: you knew with the manager at the helm you always had a chance of success.
"From first meeting him at 12, 13 up until now; he still has an influence."
Giggs believes Moyes' elevation to the Manchester United job is a shot in the arm for British managers.
The Welshman said: "I'm enjoying it, the coaching role.
"It was always going to be a big ask whoever took over, he had such a successful time at Everton I think he deserves it.
"It's great for a British manager to have this chance because historically in the last 20 years these jobs have gone to foreigners.
"I'm enjoying playing under him and learning under him as a coach as well."