Leinster head coach Leo Cullen praised the character of his side, after they fought back from 19 points behind to defeat Ulster 38-29, and maintain their 100% record in the BKT United Rugby Championship.

The leaders looked destined for a first defeat of the season when they fell 22-3 down approaching half-time, while they had also been reduced to 14 men on 20 minutes after a red card for Cian Healy.

However, after getting back into the game with a Rónan Kelleher try just before the break, they looked a new side in the second half, scoring four further tries to go nine clear at the top of the table.

"That was stressful, wasn't it?", a relieved Cullen exhaled.

"It's a pleasing win, with all that was going on in the game. Some good character, and all the rest, and that's the game, isn't it?"

Ulster looked on course for a second successive win away to Leinster when Rob Herring, Kieran Treadwell and Ethan McIlroy crossed within 15 minutes of Healy's sending off, and Cullen admits it took his side some time to adjust to their numerical disadvantage.

"The way the game is now, you have to be able to deal with that some point, a red card. Then there's a few decisions you've to make, do you go with seven forwards or eight forwards?

"We take Jimmy [O'Brien] off when Andrew [Porter] comes on, and it leaves us a bit vulnerable in the backfield, and Ulster - they kick a lot - we know we'll have to deal with the aerial threat.

"Credit to Hugo [Keenan] and to James Lowe, in terms of dealing with that aerial threat that comes from them. Ulster are very clinical, the red card happens, and we're weighing up what exactly we'll do and they dragged us over, eight forwards against seven.

Garry Ringrose scored two second half tries

"Ulster are on top during that period, we get a little bit of go-forwards, we turn the ball over and they score up the far edge. It's pretty clinical, and it's not looking great for us at that stage. Down 22-3, and credit to the lads, the score before half-time."

And the Leinster coach said his players showed huge confidence to complete the comeback in the second half.

"We go through a period where we're looking after the ball a bit better, we were a little bit loose before that. It's the big thing going into next week, you give a team like Racing those opportunities, they're pretty clinical in terms of punishing you.

"The forwards grabbed the game by the scruff of the neck in the second half and got on top, got in for a few good tries, Garry [Ringrose] finishes two tries exceptionally well, and we get the job done. It was helter-skelter at times."

It was a crushing defeat for Ulster, while it was also worrying to see the province lose three players to head injuries.

Tom Stewart departed with a blood injury after the incident in which Healy was red-carded, while Iain Henderson didn't return from a second half HIA.

The most concerning of injury looks to be John Cooney, the scrum-half having looked in a bad way when departing early in the second half after a big collision with James Lowe, but head coach Dan McFarland says it's too early to tell the extent of the injuries.

The Ulster boss was deeply frustrated with the second half capitulation, but admitted Leinster's opening try just before half-time was the crucial moment in the game.

"We obviously gave the try away at the end of the first half which game them momentum, and made some errors in the middle of the park which game them field position and a little bit of momentum which they could capitalise on," he said.

"They're a good team, that's probably the long and the short of it."