The Rebels fell behind just three plays later and could never get even the rest of the game.
Western used its big-play offense to pull away from Casey and then withstood a furious rally by the Rebels late in the fourth quarter. The Warriors (9-2) move on to face Corbin this week in the second round.
Junior Corey Goodson, ran over Casey to the tune of 226 yards and three touchdowns. He also completed one pass for 19 yards. His 245 yards accounted for most of Western's 291 yards.
"It's tough to let one guy beat you and you really don't know how it happens," Stephens said.
The loss happened because of big plays by Western and missed opportunities by Casey. The Warriors had three plays of more than 50 yards each, while Casey only had three plays go for more than 20 yards.
But the Rebels were still within striking distance with 9:16 to play, trailing 20-12. That's when Mikey Hatter recovered a Western fumble at the Warriors' 13-yard line. Two rushes by Rex Delk and an incomplete pass left Casey facing a fourth-and-four from the seven. Blake McGinnis, who finished with 154 yards rushingand three scores, was stopped short on the fourth down play, and Western went on to score on its next possession to go up by 15 points at 27-12.
"It worried me some when they scored early in the fourth to go up two good touchdowns only because we had struggled putting it in there," Stephens said. "When you've got five or six chances to score a legitimate touchdown, and you don't, that's the only thing you worry about.
"We work hard, hard, hard, hard and then we'll relax for a play or two. I think it's just relaxing every now and then and not buckling down and knowing you've got to get something done."
Aided by a 15-yard unsportsmanlike conduct penalty on the Western bench, Casey moved the ball 80 yards in five plays and got a 7-yard scoring run from McGinnis to draw within 27-18. Swango was sacked looking to throw the ball on the two-point conversion.
Western went three-and-out on its next possession and Casey took over with 1:14 to play. Another big penalty on Western, this one a 15-yard face mask call, helped Casey go 61 yards in nine plays to score again on a 7-yard run by McGinnis with only eight seconds left to play.
That got Casey within 27-24, but the Rebels were called for an illegal substitution on the extra-point attempt. Casey called for a fake kick on the next play, and Rex Delk was stopped less than a yard short of the goal line on the two-point conversion.
Casey's bloop kickoff was recovered by Western to seal the victory.
Delk picked up 129 yards on 26 carries as he and McGinnis both crossed the century mark. Swango was 2-for-7 for 45 yards passing and also ran for 22 yards on seven carries.
The Rebels' defense held Western to 12 first downs, nine fewer than Casey had, and Casey had the ball for 30 minutes, 56 seconds to only 17:04 for Western. Both teams had penalty problems, as Casey was whistled 10 times for 80 yards and Western nine times for 72.
Stephens said that despite the fact his team played its best-ever playoff game, this felt like the one that got away.
"This is one I really think we should have gotten," Stephens said.