Manchester United manager David Moyes has admitted star striker Robin van Persie makes the final decision on whether he is fit to play or not.
The 30-year old Dutchman has only featured in 17 games so far this season due to lingering hamstring and thigh problems.
He returned from a two-month injury lay-off to net the opener in United's 2-0 home win over Cardiff on Tuesday night.
Moyes said: "I have taken Robin’s advice where he feels he is at. I ask him if he is ready to play and how long does he feel he is able to play.
“All the things I am doing, I am taking from Robin. He is a player who is so important to us that I need to know exactly where he is at. Even the day he pulled his thigh against Newcastle [in December] we had said, ‘Are you better coming off the bench?’"
The United manager also feels losing the Dutch hitman for prolonged periods of time is one of the main reasons the Red Devils currently occupy seventh place in the Premier League table.
"The other night [against Cardiff], we did OK, but I won because I had Robin van Persie in the team. He is somebody who can score, who can make a difference and get you a winning goal and we have missed that," Moyes said.
“We have missed that element where, when you are not quite at your best, somebody gets you the goal. We have not had that for three months now and it has been quite tough.”
Things look much brighter for the Scot now though, with Wayne Rooney also returning in the win over Cardiff, and the arrival of Juan Mata from Chelsea is sure to boost United's chances of ensuring they don't miss out on a Champions League place for the first time in the competition's history.