Bauserman, who was held under 300 yards passing for the first time all season, directed an 11-play, 75-yard drive in response, but this would prove to be the visitors high-water mark.
De'Eric Bell, who had 227 yards rushing on 21 carries, scored the first of his two TDs at the 10:48 mark of the second and Guilford never trailed again.
A 15-yard Karsten Miller TD pass with 8:43 to play in the second push the Quakers lead to 21-13; they took a 24-13 lead into the half after hitting a 25-yard field goal on the final play of the second.
SU was able to cut the deficit to four points, 24-20, by driving 76 yards on nine plays at the 7:54 mark of the third, but Guilford answered that Michael Ashwell TD reception with a three-play, 50-yard touchdown drive and cruised home to the 25-point win.
"That was the sloppiest game we have played all year and we aren't going to win any games in the ODAC playing like that."
Bauserman, the nation's passing leader, threw for 290 yards on 37 completions in 56 attempts, but was picked off four times after entering the game with just five interceptions all season.
His yardage, completions and attempts all were enough for Bauserman to set new season records in each category. He had broken the season touchdown throws record last week versus Bridgewater.
Ashwell had 10 catches and now is the co-holder of the season receptions mark originally set by Rico Wallace '12.
SU was also 7 of 19 on third down and just 1 of 6 on fourth down.
Shenandoah steps out-of-conference next Saturday for a 1 p.m. home game versus Apprentice.