AUBURN — St. Dom’s started the Mountain Valley Conference season with an entirely new defense, and a defensive win.

The Saints used a diamond-and-one to contain Georges Valley sophomore Kennadi Grover and pull away early in the fourth quarter of a 39-26 victory Saturday in the teams’ season-opener.

Allaina Murphy tallied a game-high 17 points and 11 rebounds and Mary Caron chipped in with nine points, seven boards and stifling defense on Grover (four points, six rebounds). Jill Bradbury led the Buccaneers with 15 points.

The Saints shot 63 percent in the second half while limiting the Bucs to 18 percent from the floor. Their interior defense was particularly solid, limiting Georges Valley to just one field goal inside the 3-point arc in the second half.

“It was a new defense. I’d never used a diamond-and-one before,” St. Dom’s coach Paul Rheaume said. “The Grover girl killed us last season because we didn’t really know anything about her. I watched them during preseason and none of their other girls could really shoot.”

Georges Valley tried to loosen up the defense early in the second half when Bradbury and Katlyn Rich hit back-to-back 3-pointers for the game’s only tie at 19-19. Bradbury later hit another 3 to pull the Bucs within one, but the Saints stuck with the zone.

“They hit a couple of 3s, but I knew they were going to start missing shots again, so I stuck with it,” Rheaume said.

St. Dom’s closed the third quarter with a 9-1 run, sparked by a Murphy hoop off a Carolyn Joseph feed and back-to-back hoops by Sarah Gosselin (six points) off assists from Murphy and Joseph.

“We knew we just had to keep up the intensity and keep doing what we were doing and we’d push through,” Murphy said.

Joseph closed the third with a jumper to make it 32-23 and Caron started the fourth with a layup to put the lead into double digits for good. Grover scored the Bucs’ first field goal of the quarter to end an eight-minute drought late, but it was too late.

Caron shadowed Grover all over the court and limited her to two field goals because the Buccaneers’ top scorer never got a good look from the outside.

“I didn’t want to let her shoot 3’s. She scored a lot of points the last time we played her,” Caron said.

Georges Valley tried a junk defense of its own to try to stop Murphy — a box-and-one — and doubled down any time the Saints looked to her in the post. But the senior scored 10 of the Saints’ 11 points in the first quarter to help them jump out to an 11-2 lead.

“We tried to take the ball out of her hands as much as we could,” Georges Valley coach Dwight Henry said. “Let’s face it, she’s a good ballplayer, a smart ballplayer. When they double and triple her, she knows that she needs to get it to her other teammates and she does a good job at it.”

“We practiced it all week and came up with some new plays against it,” Murphy said. “It was tough to push through the double team. Mary and Sarah both came up big, so it was great.”

St. Dom’s got a little careless with the ball in the second quarter, allowing the Buccaneers to close to within four at the half on Bradbury’s first 3 and a Jessica Veilleux layup off a turnover.

“(Ball movement) at times was lacking. We threw a few bad passes away,” Rheaume said. “But for the most part, we know people are going to try and zone us, box-and-one on Allaina. We’ve got some other shooters out there and I think it showed.”