It might have been easy to overlook Wagner considering a Northeast Conference program had never won an FCS playoff game.
But Wagner never trailed on Saturday while it forced five turnovers in a 31-20 victory over Patriot League champion Colgate in the first round.
The Seahawks, who improved to 9-3 with a ninth straight win, were playing in their first postseason game since 1988, when the team competed at the Division III level.
The third team to represent the NEC in the playoffs, the Seahawks will travel to No. 2 seed Eastern Washington for a second-round matchup Dec. 1.
Wagner's defense stifled Colgate's dangerous rushing attack, led by quarterback Gavin McCarney and running back Jordan McCord, by holding the Raiders to just 296 yards of offense and only 177 rushing yards. The Raiders had been averaging 503.7 total yards per game.
Wagner jumped out to a 14-0 lead in the game's first 17 minutes behind a Nick Doscher touchdown pass and a Dominique Williams rushing touchdown. Doscher only threw for 95 yards, but tossed two touchdowns, became the Seahawks' all- time passing yardage leader (5,975) and upped his streak of passes without an interception to 210. He added 91 yards and one touchdown on the ground.
Williams finished with 106 rushing yards and one touchdown on 21 carries, moving into fourth place on the Seahawks' all-time rushing list. He has rushed for 100 or more yards in 20 of his 31 career games.
The Seahawks didn't commit a turnover, leaving them with just one in their last nine games.
The defense forced five turnovers from McCarney - three fumbles and two interceptions - and held Colgate's fifth-ranked FCS rushing offense (294 yards per game) and third-ranked FCS scoring offense (41 points per game) well in check.
Colgate, ranked 24th nationally, ended its season with an 8-4 record. McCarney and McCord both rushed for touchdowns, but the Raiders' 20 points were the lowest total for the team this season.