Munster used all of their big match knowhow to cling on to a half-time lead against Saracens at the Ricoh Arena in Coventry, to book their place in their fourth Heineken Cup Final against Toulouse.

Munster reached their fourth Heineken Cup final after ending brave Saracens' European adventure in a pulsating clash at the Ricoh Arena.

The Irish giants will now return to Cardiff's Millennium Stadium - scene of their 2006 title triumph against Biarritz - and an appointment with three-time European champions Toulouse on May 24.

Saracens' defeat effectively knocks them out of the qualification picture for next season's tournament, given they are struggling to secure a top-half Guinness Premiership finish with just two league games left.

And with no English team through to this season's final, it means six English clubs contesting the 2008/09 Heineken Cup and France providing seven representatives.

Saracens, temporarily reduced to 13 men midway through the second half after props Nick Lloyd and Cencus Johnston were sin-binned, pushed Munster to the limit.

They scored first through explosive wing Kameli Ratuvou, but then could not get quite close enough following tries by Ronan O'Gara and Alan Quinlan that underpinned Munster's 15-7 interval lead.

O'Gara also booted two penalties and a conversion, while his opposite number Glen Jackson contributed 11 points during an enthralling encounter when both sides expended every ounce of energy.

Saracens should take great pride from their performance - it was a colossal effort - but as with Toulouse's victory over London Irish at Twickenham yesterday, Munster had just enough experience and know-how to prevail in the white-hot cauldron of a European semi-final.

Saracens boss and former Munster rugby director Alan Gaffney fielded the same pack that outmuscled quarter-final opponents the Ospreys three weeks ago, which meant England World Cup winner Richard Hill featuring in possibly his final game before retirement.

Munster made one just change from the side that accounted for Gloucester, recalling prop Marcus Horan after he missed the Kingsholm quarter-final due to a back spasm suffered just before kick-off.

The Ricoh Arena was close to its 32,000 capacity, but Saracens stunned Munster's travelling army of supporters by conjuring a stunning try inside five minutes.

Full-back Richard Haughton ran from close to his line, but Munster looked to have snuffed out any danger when they hauled him down just 20 metres further up the field.

Ratuvou had other ideas though, and his kick into space saw him gather and send centre Adam Powell on a lung-busting run deep into Munster territory.

Like Haughton before him, Powell was tackled, yet the supporting Ratuvou reacted quickest, gathered possession and dived over, claiming a touchdown that Jackson converted.

Munster were stung into action and, although O'Gara booted an eighth-minute penalty, it came after a golden try-scoring chance went begging when centre Rua Tipoki flung a forward pass to unmarked wing Ian Dowling.

Saracens were not ruffled by the let-off, and they stormed back up the field to regain a grip on possession and territory.

Ratuvou continued to cause havoc, testing Munster's defence by roaming in from his wing at regular intervals, and the Irish side tried to regain parity through repeated forward driving.

It forced Saracens back into their own 22, and they could not prevent a defensive scrum from wheeling, offering Munster a gilt-edged chance.

And the try Munster threatened finally arrived when scrum-half Tomas O'Leary found O'Gara, who sliced through Saracens' defence to make it 8-7.

O'Gara's conversion soared high above the posts, so high in fact that both touch judges could not award it. Referee Nigel Owens opted for assistance from the video official Derek Bevan, but he also ruled against Munster.

It was the cue for Saracens to end the half as they had started it - inside Munster's 22 - yet a prolonged period of pressure came to nothing.

And Munster administered a huge blow on the stroke of half-time after powerful wing Doug Howlett's midfield break caused panic in Saracens' defence and flanker Alan Quinlan galloped over unopposed for a try that O'Gara converted.

It was a sickening blow for Saracens to concede seven points during the closing seconds of a pulsating opening period, yet Munster had suddenly established a menacing lead.

Jackson reduced the gap by landing a 43rd-minute penalty, before Gaffney made his first notable substitution by replacing tighthead prop Cobus Visagie with Samoan powerhouse Johnston.

A 20-minute downpour either side of half-time quickened an already slick playing surface, and it suited Saracens as Jackson slotted another penalty after Tipoki was sin-binned for killing possession.

But Saracens' temporary one-man advantage was immediately cancelled out when Lloyd punched Munster number eight Denis Leamy and received a yellow card.

O'Gara drifted the resulting penalty narrowly wide, yet he made amends two minutes later, hoisting Munster 18-13 ahead following blatant ball-killing by Johnston which saw referee Owens produce another yellow.

Jackson's third penalty then narrowed the deficit to two points, guaranteeing a nerve-ridden finale, but despite Saracens' inspirational skipper Neil de Kock summoning one last huge effort from his fatigued colleagues, Munster clung on amid unbearable tension. Scorers:

Saracens (7) 16 Try: Ratuvou Con: Jackson Pens: Jackson (3)

Munster (15) 18 Tries: O'Gara, Quinlan Con: O'Gara Pens: O'Gara (2)

Saracens: Haughton, Leonelli, Sorrell, Powell, Ratuvou, Jackson, de Kock, Lloyd, Cairns, Visagie, Vyvyan, Chesney, Gustard, Hill, Skirving.

Replacements: Ongaro, Johnson, Ryder, Barrell, Rauluni, Ross, Scarbrough.

Munster: D. Hurley, Howlett, Mafi, Tipoki, Dowling, O'Gara, O'Leary, Horan, Flannery, Hayes, O'Callaghan, O'Connell, Quinlan, Wallace, Leamy.

Replacements: Sheahan, Pucciariello, O'Driscoll, D. Ryan, Stringer, Warwick, Murphy.

Referee: Nigel Owens (WRFU)