Ireland legend Brian O'Driscoll is on the analysis mic for BT Sport.

He is not mincing his words about Jacob Stockdale's eyesore error.

The Ulster wing dropping the ball over the line was 'unforgivable' and a massive 'momentum changer'.

Leinster head coach Leo Cullen: "It was an amazing occasion, We are very thankful but in terms of performance we are a long way off our best. Intergrating players back in, we looked like a team that have not played togehter in a long time. We were pretty disappointed by the way we went.

"We were edgy from the start. We were charged down in the first few minutes, we rode our luck at times and feel fortunate to advance to the semi-finals."

Budge Pountney
Former Scotland flanker on BBC Radio Ulster

When I look at Iain Henderson - to put that shift in after having so much time out this season. That shows a huge amount of mental strength. He wouldn't have known what was hitting him today but he kept his body moving.

Leinster man-of-the-match Jack Conan, speaking on BT Sport:

"That was incredibly tough. It's probably the toughest game I've played in all year.

"We gave them a few easy opportunities but they put in an incredible shift for 80 minutes.

"It wasn't pretty today but championship sides go and eke out a win even when it's not pretty."

Image source, Getty Images

Cian Murtagh
BBC Sport NI at Dublin's Aviva Stadium

Wow! What an incredible cup match between two sides that know each other so so well.

Leinster - as they have done all season - found a way to win but it was not pretty.

Ulster will look back on Jacob Stockdale's missed try and John Cooney's conversion miss at the end but they can hold their heads high as they return to Belfast tonight.

Ian Humphreys
Former Ulster fly-half Ian Humphreys on BBC Radio Ulster

Credit to Leinster - that last six minutes they worked their way up the pitch metre-by-metre and didn't let Ulster get near turning them over.

Jacob Stockdale looks distraught knowing that no-try was such a big turning point.-

Leinster have made it to the last four!

But they were made to sweat and grind for every point and inch.

Leinster are up to within five metres after 28 bull-dozing phases...

Leinster are trying to run down the clock, with one-out runners.

Ulster, scared to give away a penalty right in front, are not committing men to the breakdown to stop them.

Now, the lactic has caught up with Ulster scrum-half John Cooney. He is down with cramp.

Leinster are building phases on the Ulster 22m...

Cian Murtagh
BBC Sport NI at Dublin's Aviva Stadium

What a clutch kick by Ross Byrne. The fly-half had been limping heavily for several minutes before that penalty but still had the guts to point to the posts and send it over.

He's just hobbled off now and Leinster have no recognised goalkicker for these final few minutes.

Rob Kearney has come on to replace the hobbling Ross Byrne in the Leinster backline.

It looks like Noel Reid might be slotting into 10.

On one leg.

Byrne's kick is plum through the middle.

He limp-hops back towards halfway.

Surely he needs to come off, despite that superb kick?

Penalty to Leinster on the Ulster 22m, but way out wide.

What's the call? Corner or goal?

Leinster fly-half Ross Byrne has been suffering with cramp but calls for the tee...

A massive kick coming up.

Cian Murtagh
BBC Sport NI at Dublin's Aviva Stadium

This is great stuff. Some super scores, missed chances, broken bodies and a tied game.

Next score wins?

Ross Byrne looks like he is cramping up.

Will Rob Kearney be called off the bench to fill in in the hosts' backline?

Leinster take to the air.

Ross Byrne hoists a mighty up-and-under and Jordan Larmour very nearly strips the ball from Michael Lowry.

But the Leinster man spills forward to give Ulster the scrum.