Ireland second-row Paul O'Connell believes a strong performance against England on Sunday would guarantee his place on the Lions tour.
O'Connell has been championed as a Test certainty against the All Blacks this summer and has even been touted as captaincy material, although Ireland team-mate Brian O'Driscoll is odds-on favourite to lead the tour.
A big game against England locks Danny Grewcock and Ben Kay would probably make him Sir Clive Woodward's first choice in the position, providing the outstanding Munster forward with a massive incentive at Lansdowne Road.
"Danny Grewcock has three caps for the Lions and has many more for England. Ben Kay is a big-game player and has done it time and again for Leicester.
"They're both setting the standard at the moment," he said.
"If Malcolm O'Kelly and I want to step up to the level these guys are at we need to perform against them.
"Games like this decide whether you make the Lions tour or not. You have to produce against these guys."
England flanker James Haskell insists he will be pushing as hard as possible to be back from a toe injury in time to make his case for a spot in Eddie Jones' side looking to defend their RBS 6 Nations title next year.