CHELMSFORD — In the end, four turnovers proved too much for the Billerica High football team to overcome.

In a driving rain, Chelmsford pulled off an upset with a 28-21 win over the visiting Indians in the annual Thanksgiving Day game.

The Lions led 14-7 at halftime and after BMHS tied the score, Chelmsford (5-6) scored the next two touchdowns for a 28-14 lead.

“It was a great team victory,” said Chelmsford senior lineman Thomas Brown.

With the score even at 14, Billerica (6-5) looked to be in position to take the lead late in the third quarter.

After a bad snap forced a Lion punt from the CHS 43, the Indians stopped the kick, gang tackling Lion punter Patrick McConnell before he could even attempt the kick. With a first down at the Chelmsford 23, the Indians moved six yards in two plays before fumbling on third down.

Senior Jake Brooks recovered and Chelmsford followed with a 91-yard drive to take the lead.

A 46-yard run by sophomore Dillon Dulong started the drive and a 20-yard pass to Brooks moved Chelmsford to the 23. A keeper by senior quarterback Ryan Hart on third-and-10 moved the ball to the 9 and Hart scored on the next play. McConnell’s kick made it 21-14 with 9:10 to play.

The Indians went for a fourth-down play on their next drive from the Billerica 36. Chelmsford stopped Billerica’s Griffin Bordeau after a one-yard gain, giving the ball back to the Lions.

On the next play from scrimmage, Dulong busted loose for a 37-yard touchdown run for a two-score lead with 6:42 left.

“I’m so proud of our kids,” CHS coach George Peterson said. “It’s an unbelievable finish to our season. We thought we were a good enough team to make the playoffs, but we did some things to hurt ourselves and we weren’t able to get there, but the way we finished is a testament to the type of kid we have.”

The Indians answered with a 64-yard drive that took eight plays and ended with a 21-yard touchdown pass from senior quarterback Steven Gentile to senior receiver Matt Gray.

Sophomore Dan Venezia’s extra point made it 28-21 with 3:44 to go.

Chelmsford picked up one first down, but the BMHS defense forced a punt with 1:56 to go with Billerica out of timeouts. On the punt, Billerica’s rush to block the kick just missed and a leaping Billerica player hit McConnell on his way down, drawing a flag and a first down that ended the game.

In the first quarter, after a short punt, it took just one play for the Lions to take the lead, a 33-yard run by Brooks with 1:13 left in the first quarter. It was a trick play by CHS that saw Brady Burnham run up to the ball and flip it to a group of teammates in front of the Chelmsford sideline. Brooks took the ball down the left sideline untouched into the end zone.

“It was trick play that we saw from a state championship game in Oklahoma,” said Peterson, likely sparking Google searches aplenty. “We had practiced it every single day. The first series we went out on we noticed that nobody (from Billerica) came over where (the coaches) were. We knew it was something we could use later in the game and we just waited. That’s the kind of stuff I like.”

Billerica’s Gray nearly tied the score on the ensuing kickoff, returning it 67 yards to the Lion 22. The Indians couldn’t convert, however, and turned the ball over on downs at the 14.

On the next BMHS drive, a 13-yard run by Judd Dorival moved the ball to the Lion 40 before another lost fumble by the Indians, recovered by Brown.

“You can’t fumble four times,” said Indians coach Duane Sigsbury.

The Lions turned the miscue into seven more points as Brooks caught a 9-yard touchdown pass from Hart with five minutes left in the first half. A 34-yard run by Dulong was the key play.

Billerica scored just before halftime, driving 61 yards in eight plays and finding the end zone on a 1-yard run by Gentile.

The Indians scored again with 3:24 left in the third quarter when Bordeau scored on a 36-yard run. But Chelmsford would have the final say.