Courtesy: Princeton Athletic Communications Jamie Lettire was 4 for 5 at the plate with three home runs Sunday.

PRINCETON -- With their chances of keeping Ivy League title hopes alive at stake, the Princeton softball team turned to an old friend from a season ago Sunday afternoon at Class of 1895 Field.

Knocking six home runs, the Tigers used round-trippers to come back, pull ahead and stay ahead in 4-2 and 6-5 wins over Columbia.

Princeton had 11 home runs on the season entering Sunday, a year after hitting a team-record 55 in 2008.

With the victories, Princeton improves to 10-14 on the season and 5-5 in the Ivy League. The Tigers didn't get any help from division-leading Cornell, as the Big Red completed a weekend sweep of Penn to stay four games ahead of the Tigers.

Princeton has two makeup games Monday against Columbia, starting at 3 p.m. at Class of 1895 Field, replacing Saturday's rainout.  A doubleheader sweep would bring Princeton within three games of Cornell with eight to play.

In Sunday's first game, Princeton pitcher Jamie Lettire (4-5) closed a 2-0 deficit on her own with solo shots in the fourth and sixth innings while buckling down in the circle to keep Columbia off the board.

After Princeton stranded the go-ahead run at third in the sixth inning with one out, Kelsey Quist crushed a two-out, walk-off home run to win it 4-2.

There was no need for a Princeton comeback in game two, as Kathryn Welch's fourth home run of the season was one of two first-inning runs to put the Tigers ahead 2-0 after one.

The lead expanded to 6-1 in the third with Quist's second home run of the day, a three-run shot that had to have been one of the longer home runs ever hit in the 25-year history of '95 Field. Lettire followed Quist with a home run of her own, and Princeton tried to hold on from there.

Columbia's (12-22, 2-8 Ivy) Dani Pineda tried to use Princeton's method to lead the Lions to a come-from-behind win of their own, but Columbia fell just short. Pineda hit a three-run home run in the fifth to cut it to 6-4, and put another one over the fence in the seventh to make it a 6-5 game with one out.

Michelle Tolfa (6-8) closed it out, getting the final two outs for the complete-game win. Lettire finished 4 for 5 at the plate with three home runs, giving her a slugging percentage of 2.600 for the day.