Lafayette upset Patriot League-leading American in Saturday, while Lehigh - with C.J. McCollum looking on - lost to Holy Cross.
Lafayette used a 19-4 second half run to earn a 74-62 win over the Eagles at the Kirby Sports Center.
Dan Trist had 19 points and 10 rebounds to pace Lafayette.
The Leopards went 0-9 in the first half of Patriot League play, but have gone 4-1 in the second half.
American had been 11-2 in the league heading into the game.
Lehigh lost a 72-67 decision to Holy Cross at Stabler Arena.
Freshman Tim Kempton led the Mountain Hawks with 17 points.
Lehigh drops to 6-8 in the Patriot League with the loss.
Portland Trail Blazers rookie and Lehigh grad C.J. McCollum sat courtside for the game.
The Lehigh and Lafayette women both lost on the road. Lehigh lost at Holy Cross 76-68, while Lafayette fell 72-61 at American.
For a look at the complete local scoreboard, click here.