Tottenham manager Jose Mourinho claimed his side exhibited a lack of energy due to the “sadness” of conceding a goal.
The absence of Harry Kane was immediately felt as a lacklustre Tottenham slipped to a costly defeat.
Son Heung-min was chosen to deputise in the centre-forward position, but the South Korean could not find his usual cutting edge in the altered frontline.
Carlos Vinicius looked bright after his introduction from the bench, but Spurs’ lack of potency in the final third would cost them dear with Leandro Trossard’s first-half goal ultimately proving decisive.
Speaking to the BBC after the match, Mourinho said: “We didn’t start well. They could have scored immediately when they hit the post.
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“In the first half I felt the team was probably too sad with the goal conceded and the situation. There was a lack of energy.
“In the last 25, 30 minutes they gave everything but of course with some limitations. We couldn’t score but at the same time gave them the chance to counter-attack.
“The boys showed great spirit in the second half and the boys showed they are suffering and they tried to fight against that sadness.
“They tried, so I have nothing negative to say about them. I leave the game with a good feeling about my boys because they tried hard in the second half.
“We tried everything but they defended everything, brought on another centre-back, and it was not possible for us to score.”