Barcelona coach Xavi believes Erik ten Hag has made a lot of improvement at Manchester United.
The two coaches go head to head on Thursday in the Europa League playoff at the Nou Camp in Spain.
Xavi has a lot of admiration for ten Hag's attacking playstyle, while he praised the Dutchman for having such an influence at United so quickly.
"Tomorrow is a great match," Xavi said to reporters.
"It's a spectacular tie. Both teams arrived at the best moment of the season.
"Ten Hag has changed the face of the team. It's been hard for them but they're doing a great job. He is a great coach. Reversing the situation at United was not easy.
"He makes variants in attack and defense, they work very well. He is an attacking coach and he shows it in almost every game. He is a reference for coaches who like this kind of football.
"Manchester United is a great club. They are not in the best moment in their history but there are players who are in a great moment. In recent weeks, they have had good results and it will be very hard to win the game."