The Mets are the frontrunner to sign Ruben Sierra, according to his agent, Chuck Berry, who is optimistic that a minor-league pact could be signed before the end of the week.

Berry said yesterday that the 41-year-old Sierra’s desire to play is “definite” and said he is “100 percent healthy.”

Last year Sierra hit only .179 with no homers in 14 games, going 5-for-28 with four RBIs with the Twins. Sierra was with the Yankees in 2005, 2004 and part of 2003. He hit 17 homers in just 307 at-bats in ’04.

Berry cited the Mets as being attractive since they’re an NL team, have a strong club, GM Omar Minaya was with Sierra in the Texas organization and Sierra has played in New York before.