Paul Scholes has warned Manchester United to be wary of "really talented" attacking midfielder Adnan Januzaj in Thursday's Europa League tie with Real Sociedad.
Januzaj emerged through United's academy and made 63 first-team appearances before joining Sociedad in 2017.
The Belgium international failed to truly establish himself at Old Trafford, but he has impressed during his time in La Liga.
United take on Sociedad at the Allianz Stadium in the first leg of their Europa League last-32 tie on Thursday, and Scholes has tipped Januzaj as a player who could damage the Red Devils' hopes of progression.
"Adnan was a really talented kid," Scholes said. "When I retired the first time, I was coaching him for six months. The talent no doubt was there.
"It's still there, he's doing really well at Sociedad. I think it's been a good change for him. He showed glimpses when he first came into United's first team, that he had the ability that we all knew he had.
"For some reason it just didn't work out and he's had to go elsewhere, but he's a really talented player. He's somebody we're really going to have to watch on Thursday, along with David Silva, obviously."
Only Arsenal's Nicolas Pepe (36) has attempted more take-ons in the opposition half than Januzaj (35) in this season's Europa League.
