Kevin Doyle insisted Costa Rica defender Giancarlo Gonzalez got exactly what he deserved after leaving him with five stitches in his head.

The 30-year-old Republic of Ireland striker left PPL Park in Philadelphia during the early hours of Saturday morning bloodied after Gonzalez had been sent off for elbowing him during a 1-1 draw which stretched the sentiment of the term “friendly”.

Things came to a head when the pair, who had become embroiled in an increasingly physical battle, challenged for a high ball and the defender blatantly lashed out to leave Doyle bleeding heavily and referee Raul Castro reaching for a red card.

Doyle said: "If you are going to get that angry that quickly and do that, it's not ideal in a World Cup. I think he just lost his head.

“He was upset about an earlier challenge. He tried to win a ball down the side of me by ducking in with a header, and I have caught him totally accidentally.

“I said ‘sorry’ to him at the time and I thought that was the end of it.

“A minute earlier, he had tried to do the exact same thing and missed, so he had gone back for a second go.

“I was a little bit ready for it, but I didn’t protect myself. But I am glad he was sent off because he deserved to be.”

Doyle left the stadium nursing a nasty cut, although not one which will prevent him from playing against Portugal in New Jersey during the early hours of Wednesday morning, if selected.

He said: “It was very sore. It’s fine now, the doctor has numbed it up so I can’t feel a thing.”

For all his discomfort, Doyle was able to reflect upon an impressive individual display and his first international goal for almost two years.

He could also raise a smile about his injury when he was reminded that the steps of the Philadelphia Museum of Art made famous worldwide by the Rocky films, were just a few miles away.

Doyle said with a smile: “It probably looked worse than it was, I don’t know. I haven’t been up to the steps.”

Martin O’Neill’s side weathered a lively start by the Costa Ricans, who were playing their final warm-up game before heading for Brazil, to take the lead when Doyle powered home a long-range header from full back Marc Wilson’s inch-perfect cross.

It was his first goal for his country since the 4-1 friendly victory over Oman in September 2012 and marked the latest stage in his rehabilitation after slipping out of the reckoning under Giovanni Trapattoni.

Doyle, who was starting for the first time since O'Neill's appointment said: "It was a great ball in from Marc Wilson, a brilliant ball.

“He looked up and he saw me, and a lot of the time, they can see you and they don’t play it. He put in a great ball and I managed to get a big header on it, plenty of power.

“They don’t go in all the time, but that one did. It was nice, it was nice to start.

“When you come away at the end of the season, it’s obviously nice to get a start and great for me personally to score a goal.”

However, Costa Rica showed their mettle after Gonzalez’s 41st-minute dismissal and got back into the game despite their numerical disadvantage when Celso Borges converted a 64th-minute penalty.

Robbie Keane, back in the Ireland team after missing the last four friendlies, could have won it two minutes later when presented with a similar opportunity, but his spot-kick was well saved by substitute keeper Patrick Pemberton.

Doyle said: “It was actually quite competitive. They were putting it about and you can understand it.

“If we were going to a World Cup tonight and looking to play – from their point of view, it was a big game, I suppose, for a lot of the players wanting to be in the team in a week’s time.

“They came out in the second half and even with 10 men, they played excellently, they really did, so it was probably a fair result with us missing the penalty, and we had a few chances as well.”