BROCKTON, MASS., SEPT. 29 -- It looked like bad news for DeMatha when starting tailback Seneca Coehins hobbled off the field early in the second quarter with a bruised knee. It was worse news for Brockton.

Backup Lamont Gore filled the void, carrying 21 times for 92 yards and three touchdowns as the Stags stunned Brockton, 24-6, before 5,000 today at Marciano Stadium.

Brockton entered the game ranked fourth in the nation by USA Today; DeMatha was ranked seventh. It was Brockton's first home loss since the 1985 opener.

"They came in and they simply outmuscled us," said Brockton Coach Armond Colombo. "What it came down to was that they were just a better football team than us today."

It appeared to be business as usual for Brockton (2-1) early. After stuffing DeMatha's initial possession, the home team took over at its 36. On the first play, Anthony Comer went down the left sideline for 64 yards and an apparent touchdown, but it was called back on a clipping penalty.

"When I saw him take off, I said, 'Oh, my gosh, here we go again,' " said DeMatha Coach Bill McGregor. "Fortunately we caught a break, but that Comer is one great back."

DeMatha drew first blood when David DeArmas kicked a 23-yard field goald with 5:44 left in the first half.

DeArmas "is a great weapon for them," said Colombo. "He gives them another dimension."

After stopping Brockton on the next possession, DeMatha put together a 10-play, 60-yard drive, capped by Gore's first touchdown. The 6-foot-1, 180-pound senior blasted off left tackle and crossed the goal line with three defenders on his back. DeArmas's kick gave DeMatha a 10-0 lead with 53 seconds left in the half.

It was clear by halftime that the Stags were dominating the line of scrimmage. "Brockton was playing a great game, but we have some fine people up front for us," said McGregor. "And if you can get past them, you have to deal with our linebackers, and we have four or five real good ones."

DeMatha next capitalized on a critical Brockton error. Backed up at his 9, quarterback Mark Hartsell was intercepted at the 28 by Kenley Bullard, who returned it to the 13.

Three plays later Gore went in from the 8.

Brockton went to its rushing game next, with Comer and Chris Campbell gaining 37 yards on six carries. The drive ended when Campbell was stripped of the ball and Stags linebacker Coy Gibbs, son of Washington Redskins Coach Joe Gibbs, recovered.

After stopping the Stags, Hartsell connected with wide receiver Lemar Lee for 49 yards to the DeMatha 9. Comer then carried in for the score with 27 seconds left in the third quarter. Mark Pileski's kick sailed wide right to leave it 17-6.

"We definitely came up here with a mission," said McGregor, whose team spent 8 1/2 hours on a bus Friday. "It was a tremendous experience for us."