Belgium coach Marc Wilmots blamed a "breakdown in communication" for one goal and said playmaker Kevin De Bruyne was "perhaps tired" in their 2-0 defeat by Italy in Lyon on Monday night.
Centre half Leonardo Bonucci split the Belgium defence with a pass into the penalty area from just inside his own half and man-of-the-match Emanuele Giaccherini supplied a ruthless finish to put Italy in front after 32 minutes.
“If you’re able to play an assist from 40 metres and you’ve got three centre backs there, there shouldn’t be any danger so there’s been a breakdown in communication which shouldn’t happen at the top level,” Wilmots told a news conference.
While praising the contributions of midfielder Marouane Fellaini and defender Thomas Vermaelen, he said striker Romelu Lukaku "didn't have a particularly happy night and . . . De Bruyne could do better too".
Pressed about the form of the Manchester City midfielder, Wilmots added: “If I had an explanation I’d give you one. Is the kid tired after a busy season? Yes, perhaps. He’s been training not quite at full pelt.
“(But) I think Kevin has given so much over the last four years for the national team, you shouldn’t expect me to slate him.”
Wilmots's men, now ranked second in the world, managed just two attempts on target and, for much of the game, were reduced to long-range efforts that flew wide or were charged down by a packed Italian defence, before the Azzurri broke away late on score a second through Graziano Pelle.
“We need to really club together for the next two matches,” added Wilmots, whose side play the Republic of Ireland on Saturday in Bordeaux.
Defender Jan Vertonghen said: "We're in a very difficult position now, there's a lot of pressure on us. Most of all we need to make sure we take our chances.
“It hurts when you don’t. I’m sure we have a squad that can cope. We will be ready.”
Meanwhile, Italian manager Antonio Conte claimed his side can "do great things" following the win at Stade de Lyon.
“I’ve been repeating from the beginning – and I’m not one to tell lies – that this is a group first and foremost of men, and then footballers,” said Conte.
“That’s important because in a tournament like this you need an alchemy of people who get on well together, and the biggest satisfaction for me tonight is to see how happy they all were, including those on the bench. There’s a very good spirit in this squad.
“We have big intentions and our objective remains the same, to get into the last 16. The objective is to get where we deserve to be, without any regrets. I think the fans are pleased when they see 23 footballers giving everything on the field and who are willing to spit blood.
“I cannot deny that I was very, very emotional – to be coach of a country in such a big tournament doesn’t happen every day.
“It’s something unique for the lads to wear this shirt, but I’d like to say also that with this unity of intention, we can do great things.”