Conan: We won't let Warriors get under our skin
Glasgow Warriors supremo Dave Rennie is a world-renowned coach who has drawn praise for his teams' attacking style, yet beneath the gleaming surface is a dark edge that their opponents know all too well.
It was there when Rennie was guiding the unfashionable Chiefs of the Waikato to back-to-back Super Rugby titles and it has come with him across the equator. The beauty is built on brutality.
It is a word the head coach and his team uses freely, even the fleet of foot Stuart Hogg this week said "one of our rocks is brutality".
So, Leinster know what's coming. Their shadow team endured a tough day at the office when the Warriors came to the RDS and won well last month, with forwards putting in mammoth physical efforts that broke PRO14 records.
Jack Conan watched it all from the stands. He and the front-liners haven't seen Glasgow since last season when they faced each other in Europe and in the PRO14.
In those games, it was Leinster who brought the force but there's a sense that things will be more even tomorrow at Celtic Park.
And the Kilmacanogue native is expecting a niggly, fierce game of rugby.
"I think it does work," he said of the Scots' confrontational approach. "I think it gets under people's skin and they lose focus.
"It is quite similar to what happened to us against Munster in December.
"We went down there and they got in under our skin, distracted us from playing our own game. There was indiscipline from us and that's why they won.
"Glasgow are quite similar in that sense in that they can be quite in your face.
"If you let it get to you, it is going to distract you from your job and you're not going to be focussed on the job in hand.
"We will obviously go in with the same mindset we had against Munster. We have to not let that faze us, just worry about us, celebrate our small victories and then execute our game-plan."
For Conan, that is the most important lesson Leinster need to take from the defeat to Saracens in Newcastle last month.
More than any other player, the No.8 has articulated the team's disappointment in their own display at St James' Park, the sense within the dressing-room that the Champions Cup final got away from them because of their own poor play rather than their opponents' superiority.
He was one of the team's top performers that day, just as he was against Munster last weekend, and he wants the team to stick to their principles and the game plan put in place when the pressure comes on in Glasgow.
"I think we looked back after the game and we looked at the opportunities we left out there and didn't take," he said.
"And even the style of play we had spoken about all week leading up to the final was to get to the width, make them work hard around the corner and then have two-sided tackles, and we just didn't do it.
"It was partly because of the linespeed that they brought, they put us under serious pressure so whatever about physicality in 'D', when we were in attack, we didn't do what we said we were doing and that was probably the most disappointing thing about the day.
"Something we had practised so hard on all week, and all year as it's the style of play, we never got into our attacking flow. We didn't get to the edge and we were just running into big bodies time and time again. They're massively physical lads so it's tough.
"You might eke out a few yards but we were never going to win that man-to-man physical battle.
"We didn't get the tactics wrong. We got the execution wrong.
"Defensively, Billy Vunipola and Will Skelton, on the day, were pretty unstoppable.
"In saying that, some of our tackle entry wasn't great. We went quite high on them which is bread and butter for those lads.
"They just get a rumble on and it's soft yards. If we had made two-man hits, we could have stopped them a bit better."
For all that he has looked at Newcastle critically, Conan is not one to dwell on his own form.
To most observers, the 26-year-old has hit a career-best vein of form at the perfect time and will go into Ireland's pre-World Cup training-camp as the favourite to wear the No.8 shirt in Japan.
While Joe Schmidt has been slow to reward him before, he has been an increasingly influential figure in the green jersey this season and on Saturday he out-played two of his direct rivals in Peter O'Mahony and CJ Stander.
"I'm happy enough, injury free which is the main thing," he said, modestly.
"I've played a few games the last while, I feel fit, the body is good, happy with the performances I've put in for Leinster. Hopefully keep doing what I'm doing and see what happens in the next few weeks.
"The World Cup feels like a million miles away at this stage with something still on the line with Leinster.
"At the moment it's all mentality of 'don't believe the hype, don't believe the noise'."
Another performance on Saturday would cement the impression he's in for big things in Japan; he just needs to meet Glasgow's fire with fire.
Glasgow vs Leinster
Guinness Pro14 Championship Final
Celtic Park, Glasgow; Tomorrow, 6.30pm