GAINESVILLE — Riverside Military Academy coach Chris Cotter looked at his roster Monday and realized he had a problem - he didn't have any running backs.

So, Cotter scrapped the Wing-T offense his Eagles ran in the first three games and installed a spread passing attack. It produced the most points Riverside has scored this season.

But it wasn't enough. Landmark Christian broke open a seven-point game in the fourth quarter and cruised to a 31-15 win over the host Eagles Friday.

Cotter found out Monday that his starting running back Justin Martin had withdrawn from the program, leaving him without a true backfield option. He was forced to put in a new offensive scheme centered on freshman quarterback Michael Gallup in just five days.

Gallup had attempted a total of 34 passes in the first three games. He attempted 29 passes, completing 13 for 193 yards with a touchdown and two interceptions, against Landmark.

"It was difficult," a frustrated Cotter said after the loss, adding that he'd never faced a week where he didn't have any options at running back.

The short-handed Eagles managed to hang around, though, and when Gallup connected with Omari Archibald on a 22-yard touchdown pass, Riverside found itself down only 14-7, heading into the fourth. It was the Eagles' first touchdown since Week 1, when Martin scored in a 7-3 opening win over Pinecrest Academy.

Early in the final quarter, Cotter gambled on a 4th-and-1 from his own 24. Landmark held up Gallup on a sneak and took over in scoring position.

The Riverside defense, led by Victor Salcido, kept Landmark out of the end zone. Ryan Thames connected on a 25-yard field goal to make it 17-7.

Riverside went three-and-out on its next possession, and that's when the wheels came off.

Landmark's Cantrell Frazier returned the ensuing punt 68 yards for a touchdown. The War Eagles (2-1) recovered a Gallup fumble on the Riverside 1-yard line on the next possession and salted the game away with Jake McCurry's 1-yard touchdown run with 6:34 to play.

Frazier had a big night for visitors. In addition to his game-changing punt return, the junior caught six passes for 122 yards, including a 49-yard touchdown that put Landmark up 7-0 right before half.

The War Eagles extended their lead on the opening drive of the second half on a 37-yard touchdown pass from Carson Barnett to Jake McCurry. Barnett started slow but finished with 237 yards on 16-of-26 passing.

Gallup led a late scoring drive and scrambled in the end zone for a 9-yard touchdown. He hit Chris Davis for a successful two-point conversion.

Riverside (1-3) finished with 35 yards rushing. Gallup was responsible for 30 of those on 25 carries. Cotter said that the offensive line's struggles had as much to do with the lack of production on the ground as the lack of capable backs.

"We've got to learn how to block," Cotter added.

The Eagles host George Walton Academy in their Region 8-A opener next week.