SAN JUAN CAPISTRANO — Jack Ortlieb noticed a difference in the way the Corona del Mar High boys' lacrosse team came off the bus Saturday. He said the Sea Kings lacked the energy they usually have right before a game.

They have been riding the bus quite a bit during their spring break.

The Sea Kings played at Thousand Oaks on April 13, then traveled the next day to the San Francisco Bay Area to play Danville San Ramon Valley on Monday and Pleasanton Amador Valley on Tuesday.

Wednesday marked the Sea Kings' return home. They came back without their 36-game winning streak.

In its first game back in Orange County, CdM lost again.

The Sea Kings dropped a heartbreaker at St. Margaret's, 12-11, in sudden-death overtime. Their second-half rally fell short, resulting in the second setback in six days for the Sea Kings, ranked No. 4 in the state by LaxPower.com.

Keep in mind, CdM went 24-0 last year and began this year 12-0.

You have to go all the way back to the 2011 season to find the last time CdM lost twice.

"I'm not worried," said CdM Coach G.W. Mix, whose team is 13-2. "We had two losses this week because we played two damn good teams."

Those two damn good teams, No. 8 San Ramon Valley and No. 24 St. Margaret's, each edged CdM by one goal. And they each pulled it off late.

San Ramon Valley ended the Sea Kings' 36-game winning streak. In a battle between two of state's top teams, San Ramon Valley won, 10-9, scoring the game-winning goal with 20 seconds left.

St. Margaret's scored with 24 seconds left to force overtime. Chase Williams somehow produced the goal, with defenders chasing from behind.

Williams beat the Sea Kings well before the senior recorded his only goal of the afternoon.

"Four or five guys on a groundball and I think I got lucky," said Williams, who picked up the ball and attacked. "I saw that the scrum was kind of all behind, so I just took it around [the goal]. I don't know what happened. I think I got tripped or something and I just yanked it in."

The goal was the only one CdM goalie Hoyt Crance, who made 14 saves, and his defense allowed in the fourth quarter.

But the Sea Kings gave up one more in overtime.

Joshua Davis' fourth goal with 82 seconds left in the four-minute, sudden-death-overtime period ended it. The Tartans (12-4) knocked off another of the state's upper-echelon programs.

This time, St. Margaret's, which defeated No. 10 Kentfield Marin Catholic earlier this month, got past the defending U.S. Southern California Lacrosse Southern Section champion Sea Kings. The Tartans rushed each other and celebrated as CdM looked on in disbelief.

The Sea Kings had fought back from six-goal deficits in the second and third periods. They started winning face-offs against St. Margaret's standout Ryan Harnisch, a University of Denver commit, and gaining possession.

The Sea Kings stormed back and took the lead 66 seconds into the fourth period. During a two-minute stretch that started late in the third, Ortlieb, Brett Nelson, Todd Kitzens and Casey Mix each scored a goal.

The 4-0 run gave CdM an 11-10 lead with 10:54 left in regulation. But like the Sea Kings' one-goal lead in the first period, the second one didn't hold up either.

The Sea Kings were in a position Mix vowed never to be in again after Monday, when they suffered their first loss in two years.

"It sucked. It was horrible," said Mix, who led CdM with four goals, while Ortlieb and Kitzens contributed three apiece against St. Margaret's. "We told ourselves that we're better than that. We just had to fight harder, and we did [after trailing St. Margaret's, 7-2, at halftime]. We came back and we had a couple of opportunities to win it. We just couldn't put it away.

"We never want to feel that again. Going forward, we won't because we can't. The playoffs are coming up."

Mix and his teammates have Sunday off before heading back to school on Monday. Mix said the Sea Kings have spent their spring break much differently than their friends.

"You know, it's tough being here, while all of our friends are in Cabo [San Lucas] and, you know, Palm Springs, and we're stuck here playing lacrosse," Mix said. "It's tough to get motivated, but, you know, we love each other and we want to go out and win another [U.S. Southern California Lacrosse Southern Section title], so we're going to do everything it takes."

david.carrillo@latimes.com

Twitter: @DCPenaloza