STANDISH — Bonny Eagle, the defending Class A state champion, lost its final two regular-season games, allowing a total of 54 points.

“It stunk,” said quarterback/defensive back Zach Dubiel, “but it was a great learning curve for us. That definitely opened our eyes.”

An alert defense came through Friday night as Bonny Eagle beat Biddeford 21-8 in the Western A semifinals.

The Scots held Biddeford to 156 yards while recording five sacks and two interceptions, the second one returned for a touchdown.

Second-seeded Bonny Eagle (6-3) advanced to next weekend’s regional final against Thornton Academy or Scarborough, who meet Saturday in Saco.

Sixth-seeded Biddeford (4-6), which upset South Portland last week, brought its own brand of tough defense, trailing the Scots just 7-0 after three quarters.

The Tigers contained Bonny Eagle’s 1-2 punch of Dubiel and running back Matt Smith to 109 yards.

“I thought we played incredibly hard, particularly on the defensive side of the ball,” Biddeford Coach Brian Curit said. “We gang-tackled well.

“The first time we played them (a 34-12 Scots win in the opener), Smith and Dubiel killed us with some long touchdowns. I thought we really minimized that, which kept us in the game.”

Bonny Eagle also hurt itself with seven first-half penalties for 51 yards.

Three of the penalties nullified touchdowns – although two were on the first drive, which Bonny Eagle eventually scored on anyway.

“Our offense was doing fine,” said Dubiel, who rushed for 74 yards and passed for 42. “We just have to dial it in more and stop the stupid stuff. We fix that and we’ll be fine.”

Smith’s 10-yard run on the opening drive was the only score until Cam Theberge scooted for a 36-yard touchdown and a 13-0 lead with 5:45 left.

Biddeford threatened three times in Bonny Eagle territory. The Tigers had a first down on the Scots’ 21 in the first half and lost yardage.

In the second half, two drives reached Bonny Eagle’s 11 and 10, but Biddeford again lost yards both times.

“That’s why they’re (defending) state champions. They make those type of plays when they need to,” Curit said.

Nick Thorne and Mason White both had two sacks. Luke Winslow added another.

“We really brought it tonight on defense,” Bonny Eagle Coach Kevin Cooper said, “from the pressure to the coverage, which allowed time for the pressure to get there.

“We had a couple of games where we didn’t think we played as well as we could on defense. I was very pleased tonight.”

Biddeford scored when Casey Twomey connected on a 30-yard pass to Dominick Day. Joseph Curit’s 2-point run made it 13-8 with 3:19 remaining.

The Tigers tried an onside kick but Dillon Reynolds recovered for Bonny Eagle.

Biddeford got one more chance with the ball, on its 23 with 1:17 left and no timeouts. But on first down, a pass bounced off a receiver and into the hands of defensive back Ben Malloy. He sprinted 25 yards down the sideline to score the clinching touchdown.

“I’m proud of my kids,” Curit said.

“That’s not the Sisters of the Poor we just lost to. They’re a very good team.”