The Washington Catholic Athletic Conference last season switched to a best-of-three series format for its tournament semifinals and championship, but the quarterfinals remain one game and this past Saturday McNamara delivered one of the season’s biggest surprises.

Tayler Stiles pitched a complete game and Hunter Mohler singled twice and scored both times to lead the visiting Mustangs to a 4-2 victory over second-ranked St. John’s, which had lost just one regular-season game in league play.

“We played the best game of the year — got great pitching from Tayler Stiles and we made every play,” McNamara Coach Larry Prange said. “We were super aggressive. We didn’t leave anything to chance. Our kids performed, they actually believed they had a shot. I thought in a one-game series with St. John’s, we really did have a shot.”

Mohler singled and scored on Curtis Pope’s squeeze bunt to give the Mustangs a 1-0 lead in the second inning. McNamara scored twice in the fourth as Brad Sullivan hit a run-scoring double and scored from second base on a groundout.

That would be enough as the Mustangs (10-16) advanced to the semifinals beginning Monday at St. Mary’s Ryken (14-10).

St. John’s finished 23-3.

Ryken advanced with a 5-4 victory over Gonzaga, pulling out the victory on Jarred Ford’s two-run double with the bases loaded in the bottom of the seventh inning. The Knights had lost to Gonzaga twice during the regular season by a combined 11-1.

“I guess you couldn’t have scripted it any better, with the seniors coming up and doing the job in the seventh,” said Ryken first-year coach Doug Creek, who played seasons in the majors.

The other semifinal series matches ninth-ranked Good Counsel (18-8) and Paul VI Catholic (16-10).

Good Counsel beat Bishop Ireton, 1-0, on Saturday as Kevin Doherty pitched a three-hitter and struck out nine. Anthony Vaglica’s sacrifice fly in the second inning provided the game’s only run as Cody Hagenston pitched a two-hitter for the Cardinals.

Paul VI advanced with a 5-3 victory over DeMatha as Mark Gunst threw his fourth complete game of the season, stranding the game-tying runs in scoring position in the seventh inning.