Heck, who finished the night with 131 yards on 22 carries and two TDs, scored with just 1:33 remaining in the game.
Monroeville junior Levi Anderson then intercepted a Josh Hamilton pass on the ensuing drive to seal the win.
The Eagles improved to 4-5 overall and 4-2 in the FC, while the Wildcats fell to 5-4 and 4-2.
New London was paced by Nick Thomas, who had 122 yards rushing on 19 tries and three touchdowns.
Mitchell Ott finished 6-of-12 through the air for the Eagles for 71 yards.
New London quarterbacks Josh Hamilton and Josh Dillard combined to go 8-of-18 for 82 yards.
Western Reserve 29, Plymouth 6
The Western Reserve Roughriders held the Plymouth Big Red scoreless in the first half on the way to a 29-6 victory Friday at Marsh Field.
The win puts the Riders at 7-2 overall and 5-1 in the Firelands Conference (FC).
Western’s victory puts the Riders a half-game up on St. Paul in the FC. St. Paul hosts Crestview tonight.
Theron Martz was the leading rusher for the Riders with 116 yards on 15 carries.
Mason Robson carried the ball six times and gained 46 yards. Both runners had a touchdown.
On the ground, Adam Predieri led the way with 73 yards on 12 rushes. Chance Butcher had 12 touches, gaining 47 yards. He also had 10 tackles.
South Central 28, Mapleton 20
South Central notched its third win of the season as the Trojans knocked off Mapleton 28-20 in Firelands Conference action Friday night.
South Central ran for 230 yards, as Caleb Barnett rolled for 106 on 24 carries with two scores and Michael Jenny added 100 on 11 tries.
In the final quarter, Logan Kinney darted 4 yards for a touchdown with 7:36 left in the contest to give the Trojans a 28-14 advantage.
Read more in Saturday's Norwalk Reflector and Sandusky Register.