After allowing the first batter he faced to reach base, BC High junior righthander Mike Vasil held Xaverian hitless as he shut down 21 of the next 22 Hawks he faced to lead the Eagles to a 2-0 victory Monday and to their second straight Catholic Conference championship.

“Back to back,’’ Vasil said. “It’s huge, definitely.’’

Vasil was doused with a ceremonial Gatorade bath by his teammates after clinching the conference title, and after the game, BC High coach Norm Walsh and Xaverian coach Gerry Lambert decided that the leadoff single should have been ruled an error, so Vasil was awarded a no-hitter.

“Definitely my fastball [was working] early, establishing that,’’ Vasil said. “I went curveball, offspeed for a couple of strikeouts, mixed in a couple changeups, but for the most part locating the fastball was a big part of the game.’’

Despite a lackluster nonconference record, the Eagles (8-5, 6-1 Catholic) tore through their league schedule to earn first place.

“I just think part of it is little things, we’ve been able to do enough little things in critical games,’’ Walsh said. “Anybody who has lost to us can look back and say they could have won that game easily, and we could have lost games that we won very easily. It’s just so tight.’’

Vasil, a University of Virginia commit, struck out seven and allowed just one base­runner after the first inning; senior right fielder A.J. Ryan reached on an error in the fifth for Xaverian (7-6, 2-4). Vasil improved his record to a league-best 5-0, and leads the Catholic Conference in strikeouts (37) and earned-run average (0.39).

The Eagles got ahead early, tagging Xaverian starter Dan Chapski for a run in the first. Junior Luke Murphy drove in junior Marty McCormack with an RBI double, but Chapski settled down to work an efficient complete game.

The other BC High run was unearned and came in the fourth. Senior second baseman Tim Keohane put down a sacrifice bunt with senior Kyle Brennan on second. Chapski fielded the bunt and fired to first, but nobody was covering. The ball sailed into the outfield and Brennan came around to score to give the Eagles and Vasil an insurance run.

Walsh’s biggest takeaway from his squad’s second straight conference title was that it shows the depth of the BC High baseball program.

“It’s great, especially because we have an entirely new cast,’’ Walsh said, comparing this roster with last season’s. “For the position guys to be all different says a lot about the lower levels of our program in terms of its development.’’

Belmont 8, Watertown 1 — Nate Espelin yielded two hits and struck out eight for the visiting Marauders (10-1).

Framingham 2, Braintree 1 — Sophomore Tommy Clark struck out five and allowed one unearned run and Sam Phipps drove in both runs to help the Flyers (7-4) knock off third-ranked Braintree.

Methuen 5, North Andover 1 — Brendan O’Shea (4-0) tossed a five-hitter and Jordan Perdomo had two hits and an RBI for the Rangers (11-2).

Hingham 3, Scituate 0 — Senior righthander John Maffei struck out 12 and Harrison White logged three hits for the Harbormen (6-6).

Winthrop 5, Swampscott 1 — Jack Wallace (11 strikeouts) did not allow a hit until the seventh for the Vikings (5-7).

Walpole 1, Milton 0 — Senior righthander Brian Gaughan struck out 19 and allowed just one hit over nine innings before sophomore Matt Donato won the game in relief. Charlie Auditore plated the winning run with a sacrifice fly in the 15th for the Rebels (9-3).

Franklin 1, Oliver Ames 0 — Jake Noviello struck out five in a three-hitter for the Panthers (9-3).

Newton North 1, Brookline 0 — John Grady spun a two-hitter and Dante Taylor singled home Cole Whitehouse for the Tigers (8-3).

Lynn Classical 3, Medford 2 — A.J. Luciano went 2 for 3 with a run, an RBI, and a double for the ninth-ranked Rams (12-0).

Softball

Mia Nowicki struck out a staggering 27 and belted the go-ahead homer in the top of the 13th inning as the visiting Spartans (8-1) dealt host Prep (9-1) its first loss.

Medford 9, Lynn Classical 8 — Amber Harbison had three hits with two stolen bases and Brenna Forbes had four hits, three RBIs and two stolen bases as the Mustangs (8-5) handed Classical its first loss. ‘

Woburn 4, Wakefield 1 — Emily Arrendondo struck out nine and Kelsey Qualey went 2 for 3 with an RBI for the ninth-ranked Tanners (8-1).

Archbishop Williams 11, Arlington Catholic 0 — Kyleigh O’Donnell struck out 13 in a no-hitter and went 3 for 3 with a home run for the Bishops (8-3).

Needham 10, Weymouth 2 — Julia May struck out 10 in a one-hitter for the Rockets (5-6).

Newton North 10, Brookline 0 — Madison Schaefer struck out nine for the Tigers (10-1).

Saugus 15, Somerville 3 — Emma Howard and Sadie DiCenso went a combined 8 for 10, recording two doubles apiece and seven total RBIs for the Sachems (5-6).

Old Rochester 5, Seekonk 3 — Sophomore Ashley Soares struck out seven and junior second baseman Sophie Hubbard went 4 for 4 for the Bulldogs (7-5).

Dighton-Rehoboth 7, Fairhaven 6 — Bailey Rassol hit an RBI single with two outs in the top of the seventh for the Falcons (12-1).

Concord-Carlisle 13, Wayland 2 — The Patriots (10-0) stayed perfect as senior second baseman Rachel Coffin recorded a single and scored a run.

Braintree 13, Framingham 3 — The Wamps (7-1) were led by seniors Mackenzie Hayes and Ally Dillon, who each smacked homers.

Norton 3, Medfield 0 — Kelly Nelson struck out 20 for Norton (11-1).

Kristen McDonnell, who resigned as girls’ basketball coach at Braintree on April 3, has returned to her alma mater, Stonehill, as a volunteer assistant for the 2016-17 season. “It’ll be a great place to recharge the batteries just a little,’’ said McDonnell, who guided the Wamps to a 166-25 record and two state titles in eight seasons. Braintree athletic director Mike Denise expects to fill the open position by the end of the school year.

Also, Braintree has promoted assistant Amanda Scully to head field hockey coach. Last fall, the Wamps finished 12-3-3, qualifying for the state tourney for the first time in program history. A captain as a senior defender at Bentley in 2005, Scully (nee Deppe) led the Falcons to the Division 2 national final.

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