SHERWOOD — Southern Oregon had no problem making itself at home Saturday evening at Sherwood High's Contreras Memorial Stadium. The return of quarterback Tanner Trosin and presence of a rejuvenated defense made the stay memorable.

The Raiders, ranked 25th in the NAIA preseason poll, opened their season and Frontier Conference schedule with a 31-21 defeat of No. 7 Eastern Oregon in a matchup that was originally scheduled to be played Thursday in Ashland. Unhealthy air quality prompted the move, which was announced Thursday, but around 2,000 fans turned out to watch Charlie Hall pick up a win in his first game as SOU's head coach anyway.

Trosin, a senior who missed the final nine games of 2016 and received a medical redshirt as a result, picked up where he left off by completing 21 of 33 attempts for 311 yards and one touchdown through the air, and 85 more yards and a score on the ground.

With the Raiders up 17-14 following a scoreless third quarter, Trosin shut the door on the Mountaineers in the fourth. At SOU's 18-yard line with 11 minutes to go, he completed three straight passes that spanned 50 yards and finished the seven-play drive with a 15-yard sprint into the end zone. And after the Raider defense forced a three-and-out, he found Bronsen Ader for a 74-yard touchdown reception that made it 31-14 with 7:05 remaining.

Ader finished with five catches for 132 yards, marking the second 100-plus-yard game of his career.

SOU's defense, led by CJ Jones' eight tackles and Armando Gauger's two sacks, held the Mountaineers to 294 yards of total offense — 178 fewer than the Raiders, and their lowest total against SOU since 2006.

EOU needed to travel just nine yards for its first touchdown, a three-yard rush by quarterback Kai Quinn that followed Justin Hughes' block of Jaxon Clark's punt on SOU's opening drive. The Raiders reeled off successive drives of 66 and 80 yards — capped by one-yard TD dives by Rey Vega and Michael Roots — at the end of the first quarter and start of the second to take the lead, but Quinn's 43-yard TD pass to TJ Hancock tied it at 14-all with 3:38 left in the half.

That left the Raiders with enough clock to tick off 11 more plays, and Marcus Montano's 28-yard field goal as time expired gave them the lead for good going into the locker room.

The Mountaineers were forced to punt on their first five drives of the second half, attaining just two first downs in the process. Quinn completed 10 of 22 passes for 129 yards and netted 95 rushing yards on 13 attempts. His five-yard pass to Brenden Kelly with 4:07 remaining marked the final score of the night.

The win was SOU's first in the regular season against a top-10 opponent since it opened Frontier play in 2014 by nipping second-ranked Carroll, 38-35. Meanwhile, Hall became just the fifth of 16 head coaches in Raider history to start his career with a win, and the first since Jeff Olson did so in 1996.

Roots chipped in 31 rushing yards and caught two passes for 32, while Jason Shelley totaled 56 receiving yards and Matt Boudreaux 38 to help the Raiders to a 24-12 advantage in first downs.

SOU plays the next two Saturdays on the road, starting with a tilt at College of Idaho (0-2, 0-1 Frontier) in Caldwell.