The two teams will close out the series with a doubleheader on Sunday beginning at 11:30 a.m.
Penn scored three in the first, and Politz battled through the next eight innings to earn the victory.
"Without question, this was the gutsiest performance Scott has ever had for us," Yale head coach John Stuper said. "It's not easy to keep battling when you're down 3-0 in the first on a bunch of ground ball hits. But he just kept putting up zeroes, including getting out of a bases loaded, no out jam."
Trailing 5-2 entering the eighth, the Bulldogs stormed back. Griffin Dey, the team's hottest hitter, launched a two-run homer to left and cut Yale's deficit to one. It was senior's fifth homer in the last seven games.
In the ninth, Cole Shelton reached on an error to lead off the inning and Alex Stiegler came on to pinch run for him Teddy Hague followed with a bunt, reached on an error and Stiegler advanced to second.
Hague and Stielger then advanced on a wild pitch. Pierce Blohwiak kept the rally going with a walk.
Whiteman, who went 2 for 4, singled through the left side to score Hague and Stiegler and give the Bulldogs their first lead of the day.
Politz scattered 14 hits and was aided for four double plays, including one he started in the fifth with the bases loaded and no outs. Politz began 1-2-3 double play and escaped the jam.
"He gave us a chance to come back," Stuper added of his starter. "Then we took the lead in the eighth, and they took it right back with some great situational hitting. But Scott's teammates picked him up and put up two in the ninth to take the lead again. And this time he made it stand up."
He retired the first two batters in the ninth, allowed a two-out double before the next batter popped out to first to end the game.
For the season, Politz has gone at least seven innings in seven of his eight starts. He improved to 5-2 on the season.
"He's the best I've ever had here," Stuper said. "Today was just another example of why I say that."
Report filed by Ernie Bertothy, Yale Sports Publicity