Republic of Ireland manager Martin O'Neill suggested his side contributed to their own downfall as defensive mistakes and a lack of control in possession led to a 3-0 defeat by Belgium at Euro 2016.

Ireland held a classy Belgian team out until half-time, but a lightning-fast counter-attack saw Romelu Lukaku finish sweetly just three minutes after the restart, before further efforts from Axel Witsel and Lukaku.

Having not offered much going forward for the opening 45 minutes, Ireland seemed intent on pushing forward more in the second half, but Lukaku's opener was a sucker punch, delivered from a position where it was the men in green who looked to threaten.

"The goals we conceded were pretty poor really," said O'Neill. "The first goal is a big, big moment in the match, and it's from our free-kick. They break on us, and they are capable of doing that."

Shane Long endured a thankless afternoon of physical attention from the Belgium defence, not least when he appeared to get kicked in the head from the free-kick which preceded Lukaku's first strike.

But O'Neill refused to dwell on what-ifs, saying of the incident: "I haven't seen that particular part back again, I'm not so sure the referee was going to give that anyway, but from that position I think we should deal with it better than we did do."

The huge defensive first-half effort took its toll on Ireland but, again, O'Neill wasn't using that as an excuse for Ireland's early second-half lapse. 

He said: "Of course, when you're pressing and pressing and pressing, and you're spending most of the time defending, then when you've got the ball, if you're giving it away rather cheaply, which I felt that we did in the first half, then it's coming back rather quickly.

"You're going to get tired, it's a natural progression, but that really shouldn't have affected us just after half-time.

"At 1-0 we're still in the game, you feel, and then the game becomes very, very stretched because we are trying to score, and the second goal comes from a breakaway."

Asked if Ireland needed to adopt a more 'Italian' mentality when it came to stopping breakaway attacks, O'Neill agreed, but conceded that type of cynicism doesn't come naturally to the Irish.

"That's absolutely right,"he said. 

"There was a situation where an Italian fellow did exactly that and had no hesitation in doing it, and in that particular situation we should feel that, if we are being outnumbered, that might have been something... you talk about a professional foul, but if it's not totally in your nature then it's not going to happen.