Mkhitaryan joined Manchester United from Borussia Dortmund in 2016 but struggled to break into Mourinho’s starting XI for the first few months.
The Armenia international eventually became one of Mourinho’s star performers, namely in their run to the Europa League crown.
And Winterburn believes the 28-year-old has been even more effective for United this season playing in behind striker Romelu Lukaku, rather than on the right flank.
Mkhitaryan has produced five assists so far this season, with only Manchester City playmaker David Silva setting up more goals with six.
“I think he’s an outstanding player,” Winterburn told Sky Sports.
“We’ve seen a little bit of a different role for him, he’s played in the hole as well for Manchester United, in behind the main striker.
“With that he can switch and go out to the right-hand side, if (Juan) Mata’s playing then Mata can come and play in the hole.
“I think with Manchester United they’ve got so much versatility up front now.
“I think his best position is in that hole because he’s got good ability, he’s got good pace, he can go past players and he can also run in behind as well.
“I always feel players running in behind always cause the opposition defenders lots of problems.”
