PORTSMOUTH, N.H. — Marshwood was leading at halftime, but only by two points and was not dominating Falmouth, as many expected.

Apparently even some who were wearing the home team’s purple jerseys were surprised.

“We got a good talking to in the locker room and it pumped us all up, and we realized that we’re not just going to roll teams, we actually have to play hard,” said Marshwood fullback Justin Bryant.

The Hawks rushed for 284 yards in the third quarter and scored three times in just over seven minutes to pull away for a 49-24 win in a Class B South semifinal Saturday at Portsmouth High.

No. 2 Marshwood (9-1) will play No. 1 Kennebunk (10-0) for the regional title Friday at Waterhouse Field in Biddeford. Kennebunk won 17-14 on a last-second field goal in the regular season.

No. 3 Falmouth finished 6-4.

The Hawks led 20-18 at halftime.

“I didn’t think we played with much sense of urgency in the first half,” said Marshwood Coach Alex Rotsko. “They played well, so we had a ball game.”

But not for long. The Hawks crisply drove 64 yards in five plays to open the second half, with Trevor Chase scoring from the 2.

Then came a three-and-out for Falmouth, punctuated by a third-down sack by Bryant. After a short punt, Bryant stormed through the middle for a tackle-breaking 48-yard touchdown.

Adam Doyon ended Falmouth’s next possession with another sack of quarterback Nick Mancini, setting up a backbreaking 80-yard touchdown by Chase on third-and-17.

Chase finished with 225 rushing yards, Bryant had 155, and quarterback Tommy Springer rushed for 103.

John Valentine added 92 yards on a team-high 14 carries.

With Chase and Bryant ripping off runs of 40-plus yards on the Hawks’ first possession, which ended with an 8-yard sweep around left end by Chase, it looked like the game could be headed in a similar direction as Marshwood’s 45-0 regular-season win.

But Mancini passed for 146 yards in the first half, including a fourth-and-3 fly route to Evan Lovely for a 48-yard touchdown with 32 seconds left in the half.

Mancini’s connections with Jack Kidder on Falmouth’s first drive set up a touchdown run by Coleman Allen, matching the Hawks’ 91-yard drive on their first possession.

Falmouth’s other score was a 59-yard interception return by Brady Douglass.

“I thought we played very well in the first half,” said Falmouth Coach John Fitzsimmons. “Their size just caught up to us in the second half, and three quick scores just changed everything.”