CIF SOUTHERN SECTION DIVISION I SEMIFINALS:

IRVINE — Just as the fans in the stands tried to catch their breath, Corona del Mar High junior Leslee Kaczmarek had to hold hers.

After a timeout, Kaczmarek dove underwater during CdM’s CIF Southern Section Division I semifinal against Foothill on Wednesday at Irvine High.

Nobody really noticed. Those fans and the Foothill defenders were more worried with watching the five remaining Sea Kings players, who zig-zagged in front of the Foothill goal and yelled teammates’ names.

But when Kaczmarek popped back up and took the ball from goalie Kate Baldoni, she was open and she knew what to do.

She made the trick play work, scoring from seven meters out with 11 seconds to go to lift Corona del Mar to the dramatic 7-6 win.

Corona del Mar will play Newport Harbor on Saturday at 7 p.m., marking the first all-Back Bay CIF girls’ water polo final.

“We try and yell different names so nobody notices that I go underwater,” said Kaczmarek, whose three goals led CdM (24-6). “I popped up and got the ball and scored. If it doesn’t work, then I’m supposed to pass it to Elise [Molnar], who steps out and shoots it. But they didn’t foul me, so it really worked like we planned.”

How long was Kaczmarek underwater?

“A good five seconds,” she said. “I got kicked in the head, so it took a while to get up.”

The resiliency was in all of the CdM players, who battled to a 2-1 lead after a quarter behind a strike from Carissa Dice and a power-play goal from fellow senior Allison Peotter. The Sea Kings extended it to 3-1 midway through the second quarter, when Kaczmarek scored on a six-on-five.

But defending Division I champion Foothill (23-7) wouldn’t go away easily. The Knights tied the score at 3-3 by halftime, and took leads of 4-3 and 5-4 in the third quarter.

The last Foothill lead came when junior Brittany Zwirner scored from seven meters out.

Corona del Mar tied it when junior Victoria Kennedy scored a power-play goal with 5:22 left in the game. Then, after a steal from Molnar at set, junior Heather Van Hiel skipped in a shot from the right wing for a 6-5 CdM advantage.

Zwirner scored another perimeter goal with 3:28 left, tying the score again. She and senior Emily Klug each scored three times, accounting for all of Foothill’s scoring.

Defensively, the USC-bound Klug also shut down the Sea Kings at two meters for much of the game.

“They left everything in the pool,” Foothill Coach Dave Mikesell said. “That was the best game Emily Klug has played in her four years here at Foothill High School.”

The Knights had the ball with under a minute to go and tried a similar underwater play, but Van Hiel forced a ball-under call to give the Sea Kings one last chance in regulation.

After Kaczmarek’s goal, Foothill got the ball into set but couldn’t get a shot off.

“We dodged a couple of bullets, and they dodged a couple of bullets,” CdM Coach Aaron Chaney said. “...It’s really too bad that somebody had to lose that game. That was a great water polo game. It’s tough to beat Foothill. Montebello was in the finals last year against Foothill, and we just beat those two teams [in the Division I quarterfinals and semifinals]. That’s a big accomplishment for these girls.”

Dice, a team captain, stepped up her play in the semifinal. She had scored just seven goals all year, but against Foothill she had a goal, three assists and three steals.

Baldoni also had a stellar game with eight saves.

“We all wanted it so bad,” Dice said. “Our drive to win was there, for sure. We weren’t going to let anything stop us. We all wanted to practice [today], definitely.

“We’re just stoked right now.”

CIF Southern Section Division I

Semifinal

Corona del Mar 7, Foothill 6

CdM – Kaczmarek 3, Van Hiel 1, Kennedy 1, Peotter 1, Dice 1. Saves – Baldoni 8.

F – Klug 3, Zwirner 3. Saves – Avetoom 7.

MATT SZABO may be reached at (714) 966-4614 or by e-mail at matthew.szabo@latimes.com.