MANCHESTER UNITED have been put on red alert after Antoine Griezmann revealed he could leave Atletico Madrid.
The French striker came close to moving to Old Trafford in the summer until Fifa's decision to uphold their transfer ban on the Spanish side saw him make the decision to stay.
In his biography, he wrote: "In June 2017, I extended my contract and I am now tied to the club until 2022.
"Although I haven't won any trophies, I have everything I could want here.
"What I don't want to say, however, is that I won't leave one day — I've not made this decision yet.
"Everything will depend on various factors."
Barcelona are reported to have agreed a deal in principle to sign the Frenchman, but Jose Mourinho is still expected to make pursue him in the summer.
And the Rojiblancos boss has even hinted in recent interviews that he expected his No 7 to leave.
He has just two La Liga goals all season.
He was a contender for the Ballon d'Or in 2016, but has struggled to reach those heights since.