Demetrius McReynolds had 21 points and seven rebounds and Eastern Illinois beat in-state rival Western Illinois 73-64 on Saturday night.
The Panthers (2-2) were in front for the final 33 minutes, occasionally pushing the advantage into double digits.
But the Leathernecks (1-3) stayed within striking distance and had a 9-2 run to close within 61-56 with 4:18 left.
McReynolds' jumper made it 65-56 with 2:35 left and Eastern Illinois led by no less than seven the rest of the way.
For winning the rivalry game, the Panthers took home the Old Railsplitter Trophy.
Ray Crossland had 17 points and Montell Goodwin scored 12.
Cornell Johnston and Muusa Dama added 10 points each for the Panthers.
Garret Covington had 22 points and six rebounds for the Leathernecks.
Western Illinois outshot and outrebounded the Panthers but had 21 turnovers compared to 10 for Eastern Illinois.