Corona del Mar High's Hunter Cullen (22) goes up strong for a header off a throw-in between California's Danny Garcia, left, and Valentin Cruz. (Don Leach, Daily Pilot / February 15, 2013)

COSTA MESA — The exchange between player and coach as they prepared to leave Jim Scott Stadium was telling.

"Nice goal," Corona del Mar High boys' soccer coach George Larsen yelled to senior Conor Roche. "About time, huh?"

Roche smiled and yelled back.

""I know," he said. "Seriously."

Roche, the Sea Kings' leading scorer as a junior with 17 goals, has had a frustrating senior year filled with injury and sickness. He still provided a moment on Friday night that the Sea Kings won't soon forget.

You could say he got his mojo back. His beautiful goal in the 76th minute was the game-winner, as Corona del Mar rallied to defeat California High of Whittier, 2-1, in a CIF Southern Section Division 3 first-round playoff match.

CdM, the second-place team from the Pacific Coast League, will play at Channel Islands of Oxnard in the second round Wednesday. Channel Islands upset No. 2-seeded Santa Ana Valley, 2-0, in another first-round match.

Roche was the league Offensive Player of the Year as a junior, but this year he said he missed at least 10 games with a hip flexor and sickness.

His seventh goal of the year, late in the second half, still lifted the Sea Kings. He put a series of moves on his defender near the upper right corner of the box, moving slightly more into the center before unleashing a shot with his left foot.

The shot went past California goalie Raul Cota and into the lower left corner, stunning the Condors (8-7-4) but lifting the Sea Kings (12-6-6). It had the Sea Kings' leading goal scorer, senior Jack Nowak, marveling to his teammates on the bench about the number of moves that Roche put on the defender.

"He's a really proud kid, he's a really hard-working kid," Larsen said. "The fact that his senior year has not gone the way he's wanted, I know it's been on his mind and weighed heavily on him. The fact that he could come out and score a goal like he did, his senior year in a playoff game to score the game-winner, I think that makes his season OK. That makes all the other bad stuff go away, right?

"That was his moment. For him to get that signature moment in his senior year, score a goal like that in the playoffs, I think he's going to remember that one for a long time. It was a special moment. We needed a touch of individual brilliance to break the game, and that's certainly what he brought to the table."

Roche said his hip is feeling better. He added that he has not been aggressive enough in one-on-one situations, but CdM worked on that this week in practice.

It was a satisfying end to a frustrating, physical match for the Sea Kings. They dominated play early on, racking up corner kicks. They nearly scored in the ninth minute on a series of passes, from Chris Von Der Ahe to Roche to Nowak to John O'Connor. But the shot was just wide left.

California took a 1-0 lead in the 18th minute after CdM failed to clear the ball out after a throw-in. Sophomore Cesar Nuno scored on the first good opportunity of the match for California, the second-place team out of the Del Rio League.

Roche said CdM went into a funk until halftime, when the Sea Kings snapped out of it.

"Then we were able to calm down and actually play our game," Roche said. "We knew that the goals would come, if we kept possession and kept playing our game."

CdM drew even in the 56th minute, after junior forward Jake Kim was fouled in the box. Nowak converted the penalty kick, his team-best 13th goal of the season.

The Sea Kings kept pushing, and eventually defender Daniel McCabe played the ball up to Roche in the closing minutes. Roche did the rest.

Midfielders Hunter Cullen and Max Premer generated several good chances for the Sea Kings, and defenders Von Der Ahe, Jay Damon and Davis Case also shined. Sophomore goalie Hagen Truninger made five saves and also played well, stepping up to make grabs — despite contact — on long free kicks into the box.

CdM was able to advance past the first round for the fourth straight year under Larsen. Roche said he thought the Sea Kings could have a deep CIF run in them.

"I think we can play with any team, if we put it together and keep our composure," he said.

matthew.szabo@latimes.com

Twitter: @mjszabo