|Leinster (15) 18|
|Pens: Madigan 6|
|Bath (5) 12|
|Tries: Ford, Hooper Con: Ford Pen: Ford|
Leinster took advantage of an ill-disciplined first-half performance from Bath to reach the semi-finals of the European Champions Cup.
George Ford scored a sublime solo try for Bath but five Ian Madigan penalties gave the hosts a 15-5 half-time lead.
Stuart Hooper scored Bath's second try but Madigan's sixth penalty put the hosts six points clear.
A Ford penalty cut the gap to three but a late Bath attack ended in a controversial penalty to Leinster.
The hosts, who are looking to become champions of Europe for a fourth time in seven years, were the more composed side at the Aviva Stadium in Dublin.
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|Semi-finals to be played 17/18/19 April|
And although Leinster were out-scored two tries to none, Bath have only themselves to blame after a first half filled with a toxic mixture of indiscipline and knock-ons.
When they finally cut out the penalties and the errors they looked dangerous with ball in hand, with Ford pulling the strings and Anthony Watson a real threat from full-back, but Leinster had the know-how to hold on - albeit only just.
Presented with the chance to edge clear Leinster were happy to turn to Madigan and the sometimes erratic kicker was bang on the mark on five occasions in the first 40 minutes.
Bath finally switched on when Ford dummied his away past Jack McGrath and Devin Toner in midfield and rounded Rob Kearney on his way to scoring the opening try, but he took the shine off the score by missing the fairly simple conversion.
As the first half wore on Leinster began to get the upper hand in the scrums and with Watson also spending 10 minutes in the sin-bin, Bath were probably happy to still be in sight at 10 points down come half-time.
They were better after the interval and another classy break from England fly-half Ford gave captain Hooper the chance to power over.
Ford converted and, after Madigan had kicked his sixth penalty for Leinster, the Bath number 10 replied in kind for the visitors to set up a grandstand finish.
After a stop-start encounter the final 20 minutes were thrilling and the result was settled by the final attack.
Bath thought they had won a kickable penalty to level the scores as Sean O'Brien appeared to handle in the ruck, but the visitors' replacement Matt Garvey was instead penalised for not coming in through the gate.
And once again it is three-time champions Leinster - packed with Irish Six Nations winners - who are into the last four and eyeing the biggest prize in European club rugby.
Bath head coach Mike Ford:
"There is a lot of disappointment. The first-half performance, especially, we are a lot better than that. It is probably where we lost the game.
"We couldn't really control the ball and we gave away some penalties. We made quite a few line-breaks, but there is more than one way to win a game. It is not just about scoring tries. They kicked their penalties and fair play to them.
"But we are so disappointed because we are a lot better than what we showed today. That last 10-15 minutes, I was pretty convinced we were going to win the game, but it's small margins."
Leinster: R Kearney; McFadden, Te'o, Madigan, Fitzgerald; Gopperth, Boss; Healy, Cronin, Ross, Toner, M McCarthy, J Murphy, O'Brien, J Heaslip.
Replacements: D'Arcy for R. Kearney (74), Kirchner for McFadden (41), Reddan for Boss (57), J McGrath for Healy (58), Strauss for Cronin (65), Moore for Ross (50), Denton for M. McCarthy (71).
Not Used: Ryan.
Bath: Watson; Agulla, Joseph, Eastmond, Banahan; Ford, Young; James, Webber, Palma-Newport, Hooper, Attwood, Fearns, Louw, Houston.
Replacements: T Homer for Agulla (65), Burgess for Eastmond (60), Stringer for Young (65), Auterac for James (52), Batty for Webber (49), Lahiff for Palma-Newport (57), Garvey for Attwood (62), Faosiliva for Fearns (57).
Sin Bin: Watson (26).