LONDON • Jose Mourinho rebuked his Manchester United players for lacking concentration and being too "relaxed and funny" in the dressing room, before St-Etienne were beaten 3-0 in the Europa League last-32 first leg at Old Trafford on Thursday.

The manager was delighted with the result, which was due to a Zlatan Ibrahimovic hat-trick that took the Swedish striker to 23 goals, the most in a season for United since Robin van Persie scored 30 in the club's last Premier League-winning campaign in 2012-13.

But Mourinho was particularly unhappy with his side's attitude beforehand and felt he had to change it during the half-time interval.

Saint-Etienne finished the first half strongly and substitute Nolan Roux squandered a glorious chance to level two minutes before Ibrahimovic netted United's second goal in the 75th minute.

Mourinho said United's first half had been "so bad" and, when asked why, he said it had been down to a "lack of concentration".

"I had the feeling immediately in the dressing room - too noisy, too funny, too relaxed," he said.

"Then my assistants had the feeling in the warm-up, with some of the guys not really focused on getting the right adrenaline in their bodies.

"Lack of concentration. When you don't have it, it's difficult to recover it.

"In the first half it was hard. Even myself on the touchline, it was difficult, the communication. I needed half-time. We were lucky to be winning 1-0. After that, different story, different result."

He has made no secret of the fact he would rather be playing in the Champions League than its sister competition, but he said that was no excuse for United's lack of focus.

"I know the Champions League is the competition everyone wants to play, everyone wants to win," Mourinho said. "But we don't play the Champions League, we play the Europa League. We had the group phase a little bit like this. When we needed to win, we did it."

Ibrahimovic, 35, took his tally of goals against Saint-Etienne to 17 in 14 games, but the 17th hat-trick of his career was also probably the most scruffy.

He opened the scoring with a 15th-minute free kick that was awarded for a seemingly non-existent foul on him by Jordan Veretout and his shot trickled past Stephane Ruffier via a deflection off Vincent Pajot.

His second goal was a tap-in created by substitute Marcus Rashford and his third, with two minutes to play, came from the spot after he crumpled following a challenge by Kevin Theophile-Catherine.

"People that know me know that I play in many clubs and I try to do my best," said the former Paris Saint-Germain striker, who has scored more goals against Saint-Etienne than any other club. "Wherever I went I won, so I am like Indiana Jones... hopefully I can do the same (score) next week (in the return leg on Wednesday)."

Saint-Etienne coach Christophe Galtier was unable to disguise his disappointment with Czech referee Pavel Kralovec.

"The scoreline is very harsh," he said. "I'm disappointed by the appreciation of the game and the errors by the officials, in particular the first free kick and the penalty. My players put so much into this game and they deserved to have more to play for in the second leg."

AGENCE FRANCE-PRESSE, THE GUARDIAN