JACK CONAN says losing to Scarlets was as painful as being defeated in a European semi- final — and he means it.

The Ireland and Leinster forward was part of a strengthened side that went to Parc y Scarlets last Saturday looking for a first win in Llanelli since 2013.

2 Jack Conan says defeat to Scarlets was as painful as losing a European semi-final

Leo Cullen made 11 changes to the side that beat Cardiff the week before, with Tadhg Furlong, Cian Healy, Devin Toner, Conan, James Lowe, Robbie Henshaw and Jordan Larmour all starting.

The PRO14 champs were 14-10 ahead at the break but Scarlets scored 13 unanswered points after the restart to win.

Conan, when asked if rustiness was to blame, said: “To be honest, that’s probably the mindset of a smaller club.

“That’s not a good enough excuse here, to say, ‘Ah, I haven’t played in a few months — I was this, I was that’.

2 Leinster gave up 13 unanswered points in the second half

“We walked off the pitch after losing and it felt like we had gone back a few years to where we were losing semi-finals.

“It didn’t feel like the first game of the year. It felt as important as any other game. It was a massive loss and the lads were hugely disheartened, considering the position we were in at half-time.

“Yeah, lads were rusty and it showed. But, that is no excuse. We have to be better.”

Discipline was a recurring word in Leinster’s Monday morning post-match briefing. By full-time they had conceded 13 penalties to Scarlets’ seven.

Conan admitted: “That was the biggest let-down of the game, it killed us.

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“Defensively, we weren’t where we needed to be at times but we just can’t look past the discipline.”

Conan says those post-mortems will be needed if the Blues are to retain their PRO14 and Champions Cup crowns.

He added: “We were pretty harsh on ourselves. We have to be. We want standards to be high and to drive people and be better than we were. We’re critical of each other and what we did wrong and we’re trying to be tough to be kind.”