Mater Dei vs. Santa Margarita Live Stream: How to Watch National Top 15 Showdown

The Trinity League wastes no time getting serious.

Defending California Open Division state champion Santa Margarita opens league play Friday night against perennial national power Mater Dei in one of the biggest high school football games in the country.

Santa Margarita enters 5-0 and ranked No. 4 in the latest High School On SI Power 25 national rankings. Mater Dei is 4-1 and ranked No. 15 nationally.

The Eagles and Monarchs are also No. 1 and No. 4, respectively, in the latest High School On SI CIF Southern Section Top 25.

Both teams had last week off, giving them extra time to prepare for a game that could have major implications in the Trinity League, CIF Southern Section playoffs and national rankings.

Kickoff is scheduled for 7 p.m. PT at Saddleback College in Mission Viejo. The matchup has been selected as the CIF-SS Ford Football Game of the Week and will stream live on the NFHS Network.

How to Watch Mater Dei vs. Santa Margarita

What: No. 15 Mater Dei Monarchs at No. 4 Santa Margarita Eagles
When: Friday, Oct. 2
Time: 7 p.m. PT
Where: Saddleback College, Mission Viejo, California
Live stream: NFHS Network

WATCH LIVE: Mater Dei vs. Santa Margarita on the NFHS Network

NFHS subscription required to watch. High School On SI is an NFHS Network affiliate and may earn a commission from subscriptions.

Santa Margarita Puts Perfect Record on the Line

Santa Margarita has spent the first half of the season establishing itself as Southern California's top-ranked team.

The Eagles are 5-0 and sit atop the latest High School On SI CIF Southern Section Top 25.

They also enter Trinity League play at No. 4 nationally.

Santa Margarita's rise began last season, when the Eagles won the CIF Southern Section Division 1 championship and followed it by capturing California's Open Division state title.

They haven't slowed down in 2026.

After five consecutive victories, the Eagles had last week off before beginning the portion of the schedule that will ultimately define their season.

And it starts with Mater Dei.

Mater Dei Gets Another National Test

Mater Dei enters 4-1, with its only loss coming against Bishop Gorman in Las Vegas.

The Monarchs remain No. 15 nationally and No. 4 in the CIF Southern Section despite that setback.

Now they get an opportunity to make a major move in both rankings.

Mater Dei has long been one of the standard-bearers in California high school football, but Santa Margarita enters Friday as the defending champion and the higher-ranked team.

That creates a fascinating dynamic for the Trinity League opener.

The Monarchs are trying to reassert themselves atop Southern California. Santa Margarita is trying to show that last year's championship run — and this year's unbeaten start — represent a new reality.

Trinity League Race Starts With a Blockbuster

There may not be a more difficult league in high school football.

Santa Margarita, Mater Dei and St. John Bosco are all ranked among the top 15 teams in the country by High School On SI. JSerra and Orange Lutheran are also ranked in the CIF Southern Section Top 10.

Every league game matters.

Friday's opener matters even more.

Santa Margarita can improve to 6-0 and add another major victory to its case as one of the country's elite teams.

Mater Dei can knock off the defending state champion and immediately change the shape of the Trinity League race.

High School On SI will provide California high school football coverage throughout the 2026 season, including scores, rankings and top performances.

WATCH LIVE: Mater Dei vs. Santa Margarita on the NFHS Network

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