Michael Keane said he is flattered by interest from some of the Premier League's biggest clubs but insists he is happy at Burnley.
The 24-year-old Englishman - who was sold by former United manager Louis van Gaal - has also been linked with a return to Old Trafford.
"It's flattering to see, but I'm focused on Burnley," Keane said. "We've got nine games left in the season and we need to make sure we remain in the league.
"But to see things like that can only mean you're playing well."
England (@England) March 22, 2017
Keane added: "I always thought, personally, that I was going to make it at United. A few changes in managers didn't help, so when I left, I felt like I had a point to prove.
"If anything [leaving United] made me work that bit harder. I'm thankful to [manager] Sean Dyche at Burnley for the work he's done with me and the faith he's put in me - that's what has got me to where I am today."