It has been 22 years since the top-seeded team in the Southern Section's large-school division went on to win the championship.
Top-seeded Diamond Bar (27-1) is hoping to change that.
The Brahmas won their third consecutive playoff game Friday, a 7-2 victory over Long Beach Jordan (17-7) in a Division 5-A quarterfinal matchup at Jordan.
Next up for Diamond Bar is Placentia El Dorado in the semifinals Tuesday at Cal State Fullerton.
Senior Jared Janke went the distance for the Brahmas, giving up three hits to improve his record to 10-0. He also had a double, one of 11 hits for Diamond Bar.
In other playoff games:
Long Beach Millikan 8, Simi Valley 5--Despite finishing third in the Moore League, defending 5-A champion Millikan (20-5-1) continued its roll in the playoffs.
The Rams, who have eliminated Simi Valley (21-7) three of the past four years, broke a 2-2 tie at Simi Valley with three runs in the fifth, then put the game away with three more in the sixth.
Placentia El Dorado 13, Santa Ana Mater Dei 3--Shawn Holcomb picked up his second playoff victory by pitching five strong innings to lead El Dorado (23-5) in this 5-A game at home.
Mater Dei (23-5) had outscored its two previous playoff opponents, 24-0.
Covina Northview 9, Upland 5--Dave Hernandez hit two home runs, including a grand slam in the fifth inning, to lift Northview (19-5) to a 4-A victory at Upland (19-7).
Ontario Chaffey 1, Whittier La Serna 0--First baseman Fred Gomez hit a one-run single in the top of the fourth inning to lift Chaffey (17-10) to a 3-A victory at La Serna (14-6).
Gomez's line-drive up the middle scored Mario Majera, who doubled earlier in the inning.