"We got down 13 or 14, and the guys just decided we can't lose this one, senior David Weaver said. "It was very satisfying. This team is tired of losing to teams less talented than us."
Grancio and Snowden notched 23 of the Crimson's first 29 points in the second half while the outside shooting continued to struggle (0-for-7 on second-half three-pointers).
Despite Harvard's perimeter shooting woes, Penn continued to play straight-up man-to-man defense and did not double-team on Snowden or Grancio as the two scored almost at will against Penn's inexperienced underclassmen post players.
"I'm surprised that [Penn] let [Grancio and Snowden] go one-on-one with their freshmen, Weaver said. "Kyle ate them up inside, and we all fed off that."
Penn coaches made no apology for the defensive scheme and gave credit to the Harvard team.
"We were hoping to play solidly defensively", Penn coach Fran Dunphy said. "We were a little worn down after [Friday night at Dartmouth], and we knew we were in for a tough night."
But while it was Snowden and Grancio who pulled Harvard to within reach, the Crimson's last four buckets in regulation came from guard tandem of sophomore Tim Hill and senior David Demian.
Demian made two jumpers in the final two minutes to allow Harvard to set up one final play to tie.
Hill and Snowden worked an isolation play on the left wing, but Penn effectively denied the interior feed and forced Hill to create his own shot as time expired.
"Our first look was inside, but Penn did a great job defensively, so Tim had to take the shot, and fortunately, it dropped," Sullivan said.
Garett Kreitz led the Quakers with 20 points, including four three-pointers.
The win exorcises one of the last remaining ghosts haunting Harvard's Ivy League stature, and sets the team on course to finish second in the Ivies for the first time in almost anyone's memory.
Despite a 14-9 record, the Crimson had been soundly defeated in all three of its previous games against Penn and Princeton, including two big losses during an embarrassing road trip this February. But Saturday, Harvard finally proved it could play with the big boys.
"Our players thought we should be in the upper half of the Ivy League and thought they could play with Penn and Princeton," Sullivan said. "They wanted to prove that tonight."