Marc Wilmots claims he is at a loss to explain the poor performance of Kevin De Bruyne in Belgium's 2-0 loss to Italy at Euro 2016.
The Manchester City star struggled to make an impact at Stade de Lyon on Monday, as goals from Emanuele Giaccherini and Graziano Pelle consigned Europe's highest-ranked team to a defeat in their opening game of the European Championship.
Asked for an explanation of De Bruyne's peripheral role in a potentially damaging defeat, Wilmots said: "I don't know how to answer you.
"If I had an explanation I'd give you one. Is the kid tired after a busy season? Yes, perhaps. He's not quite been at full pelt in training but he's been preparing for this fixture.
"Kevin has given so much for the national team over the last four years that you shouldn't just expect me to slate him. That's why I left him on the field. He's always capable of scoring a free-kick, banging it in from range or providing an assist."
Italy opened the scoring against the run of play when defender Leonardo Bonucci picked out Emanuele Giaccherini with an inch-perfect forward pass, cutting out Belgium centre-back Toby Alderweireld and leaving goalkeeper Thibaut Courtois exposed.
"We didn't [give up] too many chances but then we conceded from a ball over the top. Three versus one, that's an individual mistake, obviously," Wilmots said of the first goal.
"If you're able to play an assist from 40 yards and you've got three [defenders] there, typically there shouldn't be any danger, so clearly there's been a communication breakdown, which shouldn't happen at the top level.
"And it put us in a more difficult position, because then we had to come out and force the game and the Italians started to really regroup at the back. If you watched the game as I did, in the second half they almost had 10 men behind the ball.
"It's difficult to play like that. They tried to hit us on the counterattack. They were pretty much there on the sofa... they were pretty relaxed."
With matches against Republic of Ireland and then Sweden to come, Wilmots acknowledged his team have little room for error left if they are to progress to the knockout stages from Group E.
"If we concede mistakes like that we'll be punished for it," he said.
"And if we can't take our chances we won't be able to win games either. But nothing is over. If we win our remaining two matches we'll still get through the group stage, which is our main objective, and that's what we'll try to do."