Keelah Dixon ended Braintree’s win over Andover Saturday with an emphatic block under the hoop — a fitting conclusion to a game the junior guard dominated from the opening tip.

Dixon poured in 21 points to propel the top-ranked Wamps to a 54-45 victory in the opening game of the Division 1 girls’ semifinals in the Comcast/Arbella Tournament at Woburn.

“[Dixon] does a great job playing within the system,’’ Braintree coach Kristen McDonnell said. “I think she took the shots when they were there, she didn’t force shots, which I thought was great. She got us started out of the gate well.’’

Braintree held Andover to just 1 point in the first quarter, with junior forward Jillian Webber sinking a free throw late in the frame.

“I think we were just really focused on really putting pressure on them, playing our good man-to-man defense, just hustling to the ball, not letting them get easy shots,’’ Dixon said.

Webber scored a game-high 24 points to lead Andover, which was without standout junior Alyssa Casey. The Golden Warriors have been playing without Webber and Casey for much of the season because of injuries, and Andover’s 5-13 record is reflective of just how crucial the two 6-footers are to the team’s success.

“They just got back their other best player, who was definitely the best player out there on the court tonight, Jillian Webber, so I think she gave them a big lift,’’ McDonnell said. “If she had been there all season, and their other best player had been there all season, they’re a much different Andover team.’’

Braintree (17-0) will play Woburn, which defeated Quincy, 60-58, in the final Monday afternoon.

“Our first half was great, our second half was not so great,’’ McDonnell said. “I think the nice thing about our team is that we couldn’t hit a lot of shots in the second half, and I thought they just grinded, got the scrappy plays, got some big rebounds. And luckily we got out of here with a win.’’

Watertown 49, Medfield 35 — Shannon Murphy scored 15 points and Nicole Lanzo added 12 to lead the 10th-ranked Raiders (17-2).

Boys’ basketball

BC High 70, Charlestown 52 — Junior guard Carl Pierre scored 21 points for the Eagles (10-6).

Medford 49, Boston Latin 46 — Sophomore guard Tyler Holness led all scorers with 18 points for the Mustangs (3-15).

Newton South 64, Xaverian 47 — Andrew Bereket led the way with 17 points for the Lions (14-5).

Boys’ hockey

Minuteman 3, Salem 3 — Freshman forward Devin Cotter had a goal and an assist for Minuteman.

St. John’s Prep 5, CM 2 — Down, 2-1, St. John’s Prep (13-2-3) scored four straight goals, the last an empty-netter by Kyle Hentosh, to win the Derek Hines Memorial game.

Hingham 4, Archbishop Williams 1 — The Harbormen got goals from Gary Betts, Marc O'Rourke, Jeff Gordon, and Steve Jacobs and will face Arlington Catholic Monday in the semifinals of the Buddy Ferreira Classic in Falmouth.

Bishop Feehan 5, Stoughton 1 — Kyle Brown scored two goals for the visiting Shamrocks.

Girls’ hockey

Duxbury 4, Whitman-Hanson 1 — KC Williams scored two goals as the Green Dragons qualified for the tournament with their 10th win.

Watertown 1, Wakefield 0 — Sophomore goalie Joanna Kennedy stopped all 35 shots and Aurora Fid­ler, a junior left wing, provided the game’s lone goal for the Raiders (6-10-1).

Nobles 2, Westminster 0 — Sophomore forward Abby Volo and junior forward Becca Gilmore provided the offense with a goal each for the Bulldogs (23-1-1).

Masconomet 7, Chelmsford 3 — Izzy Sarra scored four goals to lead the Lady Chieftains (9-6-1).

Marblehead 6, Oakmont 2 — Isabell Amigo had a hat trick and Sydney Cresta added two goals and an assist for Marblehead.

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