The win improved Penn's record to 10-7 overall and 3-0 in the Ivy League. Yale, which opened its league season with three consecutive wins for its best start since 1962-63, is 5-13 and 3-2.
On a night when two-time all-Ivy guard Michael Jordan took only five shots for the Quakers, 6-foot-11 reserve forward-center Oggie Kapetanovic led Penn with 12 points. The 6-0 Jordan scored 10 points. Center Geoff Owens (11 points, 10 rebounds) and guard Matt Langel (12 point) also scored in double figures.
But as has been the case in their recent outings, the Quakers' calling card was defense.
Penn held Yale's two top scorers, 6-11 center Neil Yanke and 6-2 guard Onaje Woodbine (10), to a combined 12 points. And the Bulldogs managed to shoot only 23.7 percent from the floor: 20.7 in the first half and 26.7 in the second half.
"I thought they were very good defensively," said Jones, who was an assistant coach at Yale from 1995 to 1997. "They had a good idea of what we wanted to do, and they contested every shot."
Yale, with six victories over Penn in the last 11 years, had come out on top against the Quakers more often than any team in the Ivy League except Princeton during that span. Last season, however, Penn defeated Yale twice for the first time since 1994-95, after the Bulldogs battled to a 71-70 overtime victory the previous year.
Last night, any Yale success against Penn seemed to be a distant memory.
The Bulldogs were down by 31-13 at halftime, and when they scored on three straight possessions midway through the second half, it amounted to a rally.
Penn had a 50-25 lead with fewer than six minutes to play. Yale had been to the free-throw line only three times. Penn's man-to-man defense didn't allow the Bulldogs to do much else, either.
Ugonna Onyekwe and Owens each blocked three shots.
"Our defense was very good," Penn coach Fran Dunphy said. "It's hard to score inside against us with those two guys blocking and changing shots. Our man-to-man is something we're counting on."
"That's our focus when we come out," Owens said. "Shut the other team down and slowly build our lead."
Yale had entered the game tied with Brown for third place in the league, behind Penn and Princeton, and was hoping to gain ground on the leaders before the weekend was over. The Bulldogs will host Princeton tonight while the Quakers will travel to Providence, R.I., for a meeting with Brown.
Jordan, the reigning Ivy League player of the week after providing the decisive points in Penn's wins over Cornell and St. Joseph's, highlighted the first half by penetrating the lane.
Jordan assisted on three straight baskets - a layup by Langel, and dunks by Onyekwe and Kapetanovic - to help Penn get going early.
The Quakers had a 10-7 lead with 11 minutes, 39 seconds remaining in the first half, and the score was 16-7 with 7:07 on the clock.
"I just go out and rebound, make some shots, and do my job," said Kapetanovic, who had two baskets at the break. The transfer from Brown will face some of his former teammates tonight.
Yale, which all too often was left to put the ball up to beat the shot clock, went 6 for 29 during the first half.
Yanke, a 10.8-points-per-game scorer who had 29 points and 13 rebounds against Brown in the Bulldogs' last outing, had a tough time contending with Owens, Onyekwe and Kapetanovic. He finished with two points on 1-of-7 field-goal shooting.
Yanke was 1 for 6 at intermission, and Woodbine, Yale's leading scorer entering the game at 14.7 points an outing, was 1 for 9.
Penn went 10 for 22 from the floor in the first half, when Owens and Onyekwe each had eight points to top all scorers.
The Quakers were making it look easy, and by the three-minute mark of the second half, all of Penn's starters had been replaced. The score at the time was 58-31.