It's a tough game to call, so ercrugby.com asked some of the biggest names in rugby to give us their predictions about who is going to lift the Heineken Cup at Twickenham Stadium today.
New Zealand World Cup winning coach Graham Henry is backing Brad Thorn to pick up another winners' medal, while Tommy Bowe is, naturally, backing Ulster.
Take a look and see what you think. You is right and who is wrong with less than two hours to the big kick-off.
Graham Henry (World Cup winning coach)
"It's Leinster for me because their players have the experience of being there before in Heineken Cup Finals. And of course, that Kiwi connection with coaches Joe Schmidt, Jono Gibbs, Greg Feek and players Isa Nacewa, Matt Berquist, Isaac Boss and the World Cup winning indestructible great, Brad Thorn."
Paul O'Connell (two -time Heineken Cup winner)
"I think I'd have to go for Leinster because of their great experience."
Lawrence Dallaglio (two-time Heineken Cup winner)
"Leinster start as overwhelming favourites. They were the outstanding team in the qualifying stages and played some exceptional rugby
"They are a side packed full of quality whose marquee players are playing very well. I get the feeling they have a bit more big match experience that Ulster, but it would be foolish to write-off their opponents."
Tommy Bowe (Ireland and Ospreys wing, who is returning to Ulster this summer)
"Two week's of Leinster losses would be perfect. I'm hoping to go to Twickenham and will have my fingers crossed for Ulster. They will go into the game as underdogs but when it comes to a final anything can happen.
"The way they have been playing and defending has been something else. Ulster are a very ambitious club and they are going places."
Bernard Lapasset (Chairman of the IRB)
"The Heineken Cup continues to go from strength to strength and I am sure there will be an incredible atmosphere at Twickenham on Saturday. It is always difficult to pick a winner in what is an incredibly competitive competition and both sides are worthy finalists.
"So I will say that I hope for an exciting game that showcases our great game and most of all I hope that the supporters enjoy their big day out. Bon Chance to both teams!"
Eddie O'Sullivan (former Ireland and USA Eagles coach)
"It's hard to look past a Leinster victory, but it will be a lot closer than most people expect. If it is close with 10 minutes left it could go either way."
Rob Howley (2004 Heineken Cup winner and Wales coach)
"I think it will be a really closely fought final with Leinster potentially just edging. They are the ones with the greater experience at this level and at the moment are the form team in Europe. However, we all know Heineken Cup finals are one-off occasions."
Nathan Hines (winner with Leinster in 2011 and losing semi-finalist against them 2012)
"I don't know how the game is going to work out, but it would be difficult for me not to go for Leinster. They are on a bit of a run and haven't lost in Europe since ASM Clermont Auvergne beat them in the Pool stages last season.
"Ulster have surprised everyone this season and pulled out some massive wins. They were very tough up front against us and they will relish the big occasion."
