Leinster came back from 17-3 down to defeat Exeter Chiefs 22-17 in an entertaining Champions Cup fixture at the Aviva Stadium on Saturday.
In a tough and uncomprimising encounter which was characterised by numerous brutal collisions, Exeter held the lead for long periods although superb goalkicking from Isa Nacewa kept Leinster in this match before a late Luke McGrath try sealed their win.
The result means Leinster have won all four their matches in the competition so far and they are sitting pretty at the top of Pool Three, five points ahead of Montpellier who beat Glasgow Warriors earlier on Saturday.
The Chiefs made a terrific start and after taking the ball through several phases from the kick off, Sam Skinner barged over from close quarters for the opening try in the second minute.
Gareth Steenson added the extras which gave the visitors a 7-0 lead but more worrying for Leinster was seeing Johnny Sexton leave the field for a Head Injury Assessment after taking a heavy knock in the build-up to Skinner's try.
And to make matters worse for the hosts, Sexton failed that HIA with Ross Byrne coming on to replace him. Five minutes later, Leinster were dealt another blow when Byrne too had go off for a HIA after a clash of heads with Nic White although he would return to the playing field later on.
The home side were putting pressure on Exeter by taking the ball through the phases with their forwards and eventually opened their account in the 17th minute courtesy of a Nacewa penalty.
Leinster's problems worsened in the 18th minute, however, when Cian Healy was yellow carded after television replays showed him shoving his forearm into the face of Luke Cowan-Dickie at a ruck inside Exeter's half.
The Irish province did not concede any points during Healy's stint in the sin bin although a Steenson penalty – after Leinster were blown up for illegal scrummaging – in the 29th minute, extended Exeter's lead.
Shortly afterwards, the Premiership champions hammered home their dominance when Cowan-Dickie crossed the whitewash off the back of a line-out drive deep inside Leinster's 22.
Steenson converted, which meant Exeter led 17-3, but the home side suffered another setback when just before that kick, Scott Fardy was also sent to the sin bin for deliberately collapsing the maul from which Cowan-Dickie scored his try.
But despite playing with 14 men, Leinster finished the half stronger and two further Nacewa penalties meant they were still in this match as the teams changed sides at the interval with Exeter holding a 17-9 lead.
Leinster came out firing after the restart and spent most of the first 10 minutes of the second half camped inside Exeter's half but could not add to their points tally during this period.
They did not panic, however, and narrowed the gap to two points by the 65th minute thanks to two further penalties from Nacewa.
And two minutes later, they took the lead for the first time when Dan Leavy made a telling line break before getting a pass out to McGrath on the edge of Exeter's 22. McGrath still had work to do but stepped out of a desperate cover tackle before crossing for a deserved try under the posts.
Nacewa added the easy extras which gave his side a five-point lead and although Exeter launched several attacks during the last 15 minutes, Leinster kept their composure on defence and held on for a memorable victory.
Pens: Nacewa 5
Yellow Cards: Healy, Fardy
Tries: Skinner, Cowan-Dickie
Cons: Steenson 2
Leinster: 15 Rob Kearney, 14 Fergus McFadden, 13 Garry Ringrose, 12 Robbie Henshaw, 11 Isa Nacewa, 10 Johnny Sexton, 9 Luke McGrath, 8 Jack Conan, 7 Josh van der Flier, 6 Sean O’Brien, 5 Scott Fardy, 4 Devin Toner, 3 Tadhg Furlong, 2 Sean Cronin, 1 Cian Healy
Replacements: 16 James Tracy, 17 Jack McGrath, 18 Andrew Porter, 19 James Ryan, 20 Dan Leavy, 21 Jamison Gibson-Park, 22 Ross Byrne, 23 Jordan Larmour
Exeter: 15 Lachlan Turner, 14 Jack Nowell, 13 Henry Slade, 12 Ian Whitten, 11 Olly Woodburn, 10 Gareth Steenson, 9 Nic White, 8 Sam Simmonds, 7 Matt Kvesic, 6 Don Armand, 5 Sam Skinner, 4 Mitch Lees, 3 Tom Francis, 2 Luke Cowan-Dickie, 1 Ben Moon
Replacements: 16 Jack Yeandle, 17 Alec Hepburn, 18 Harry Williams, 19 Jonny Hill, 20 Tom Waldrom, 21 Will Chudley, 22 Sam Hill, 23 James Short
Referee: Pascal Gauzère (France)
Assistant referees: Maxime Chalon (France), Jean-Luc Rebollal (France)
TMO: Eric Gauzins (France)