Leinster v Glasgow Warriors, Guinness PR12: Leinster flanker Sean O’Brien admits it was tough to watch from the outside as his team-mates fell to a 27-22 defeat at the hands of Clermont Auvergne in the semi-final of the Champions Cup last Sunday.

A hamstring injury ruled the Carlow native out of contention for the crunch European encounter in Lyon, but while he was left to ponder what kind of impact he may have had, he believes there were a number of positives Leinster could take from the game.

“It was very tough to watch because they are the games you want to be playing in. They are the games you work so hard for all year. We didn’t start the game like we should have. When you are sitting at home thinking you could have made a difference, it is hard to take,” O’Brien remarked at the launch of Bank of Ireland Leinster Summer Camps.

“We had a good meeting on Monday about it and the learnings we will take from it. There were positives. We played unbelievable rugby for 50 minutes and ran them around the place. If we can sustain that for the full game, especially in big games like that, it leads to an awful lot.”

O’Brien had felt tightness in his hamstring in the days leading up to Sunday’s game, and although it loosened up considerably over the weekend, he revealed it would have been too much of a risk to play in such a pivotal fixture.

“It’s one of those things that could get bad if you pushed it. When I first felt the tightness, I thought it would be fine, it would go away. It didn’t really go away on the Thursday, Friday. [I’m] back running this week. We’ll see how it is. It loosened pretty well over the weekend. It was a bit risky to play last weekend.”

A hamstring tear sustained in Ireland’s defeat to France in the 2016 Six Nations Championship sidelined O’Brien for a total of eight months, but this injury is to his other leg. While this was a source of frustration for the 30-year-old, he was relieved he didn’t suffer additional damage to last year’s injury.

“It’s not the same. It is the other side, just higher up. It was fairly frustrating last week. If it is a recurrence of a bad hamstring tear that you’ve had, you know, it’s not going to be great. I was glad it wasn’t a tear as such, just very tight. There was relief it wasn’t the same hamstring.

“There is no point in rushing it now. It would be a different story if we were in the Champions Cup final. You might push it a bit harder. It is about managing it, making sure it is 100% right to go back and play as best as I can.”

Along with four of his provincial team-mates, O’Brien has been selected in a 41-man British & Irish Lions squad for the summer tour of New Zealand. The Tullow man featured for the Lions against Australia four years ago, and is honoured to once again be selected by Welsh head coach Warren Gatland.

Before then, Leinster will be aiming to get O’Brien up to speed for their home Guinness PRO12 semi-final, but O’Brien doesn’t see a conflict between that and his preparation for the Lions tour.

“It is a massive honour, an honour for us all in the club. I’m delighted, but there is a lot of rugby to be played between now and then. I don’t think there is a conflict. If I’m back fit at the end of this week, for instance, I’ve ticked all the boxes, hit all my targets. That is me ready to go back, and they know that.

“If I’m not feeling the way I should be feeling going into a game, they’re not pushing me towards anything. They have my best interests at heart too. There is no point going out for them and pulling up after 20 minutes and be gone for the semi-final, the final or, potentially, the tour,” O’Brien added.

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