Brian McLaughlin's hopes aren't helped by a crippling injury list that has seen them lose Ireland internationals Stephen Ferris and Andrew Trimble along with South African wrecking machine BJ Botha.
But while the odds are stacked against Ulster repeating their 2006 Magners League triumph, hooker Best maintains his side won't be daunted by the challenge having booked their play-off place with a 20-13 defeat of the Dragons at Rodney Parade.
"Leinster are a top team and they are not in the Heineken Cup final for no reason," said Best, who started every game of this year's RBS 6 Nations for Ireland.
"We're going down to Dublin as Magners League semi-finalists, but we're not going to settle for that. We go there full of confidence as we have only lost four times in 2011.
"We have worked hard over the last month after the disappointment of the Northampton game to get ourselves in a position where we came to Rodney Parade to get a win and put ourselves into the semi-final. That is exactly what we have done.
"Rodney Parade is a very hard place to go and we knew that. Two of the top five teams (Ospreys and Scarlets) in the league came here in the last month and lost. We ground out a result."
For Leinster, winger Shane Horgan, who scored three tries against Ulster this season, misses out with a minor injury while the match marks Ireland captain Brian O'Driscoll's 150th Leinster appearance.
Joe Schmidt is able to name a starting XV boasting 12 Ireland internationals which will pit international regulars Mike Ross and Cian Healy against Tom Court in the front row.
But 30-year-old Court, who was used as a replacement in every one of Ireland's 2011 Six Nations matches, refuses to be intimidated by Leinster's stellar reputation.
"Leinster are playing fantastic rugby, but if you get on top of them early I think they'll realise they're not as good as everyone tells them they are," said Court.
"They are definitely beatable we saw that against Munster.
"There's always going to be a battle on two fronts from a team perspective and a personal perspective.
"I think the personal battle is a good thing as it brings more out of you so that you can put a face to a jersey and have a direct opponent.
"It maybe gives you something more to imagine in the week or two leading up to it and I think it can only help."