Clinton — It was bad enough that Old Lyme's five-goal lead over North Branford had quickly eroded to just one with a little four minutes left in Thursday’s Shoreline Conference girls' lacrosse final.

Moments later, senior Sydney Cowell, she of the 300 career goals (yes, 300), had to leave the game after taking an inadvertent kick to the face.

All was well for the Wildcats. Really, all was well.

Senior Anna Mesham scored an insurance goal seconds after Cowell went to the sideline, and classmate Hannah Guenther followed with a point-blank save on a free shot as Old Lyme successfully defended its title with an 11-9 win over the Thunderbirds at the Indian River Complex.

“I don’t think we were nervous,” Mesham said. “I think that we have amazing talent on the team, and we knew we could win.”

Wildcats head coach Emily Macione said, “We had people who were ready to go to fill that spot for a minute until (Cowell) was ready to come back in.”

Cowell scored five times for Old Lyme (16-2), which beat North Branford in all three meetings this season. Mesham had three goals and two assists and Guenther had 13 saves.

Senior Laura Quaratella added two goals and classmate Abby Berger had a goal and an assist.

Sydney Hogan and Adriana Ingarra scored three goals apiece for the Thunderbirds (14-4).

The Wildcats led 10-5 with nine minutes left when the Thunderbirds began shelling the net. They scored four unanswered goals to cut Old Lyme’s lead to 10-9 with four minutes, 1 second remaining.

Cowell got tangled up, fell, and took a foot to the noggin with 3:58 remaining. The officials ordered her to go to the sideline. Mesham scored an unassisted goal 10 seconds later.

“I’m usually more of an assist-er,” Mesham said. “I don’t usually drive all that often. I think when the pressure is on to win, we all try to get our goals, but it’s not my intention to go straight to the goal.”

Cowell said, “Let me tell you — Anna is the most aggressive, feisty person on the team. If there’s a ball near her, you know she’ll get it. She’s the first to it. She’s an awesome teammate to have. … She plays strong, she has a purpose on the field, and she really presents herself that way.”

Cowell had given the Wildcats a 10-5 lead when she scored her fifth goal, which just happened to be the 300th of her career.

“The past four years, I’ve been lucky enough to have such a wonderful team, (teammates) I can trust,” Cowell said. “I can’t just do this by myself, you know? It all happens with teamwork.”

Macione said, “Sydney came in (to high school) with a great skill set, and lacrosse is her first love. And I think she’s a goal-setter. When she reaches a goal, then she’ll set a new goal for herself. She’s not someone who’s satisfied with just doing okay. ... She wants to be great, and she pushes herself to be great as much as she can.”

The Thunderbirds had a chance to score on a free shot with 2:21 left, but Guenther stoned them.

“She had an excellent, excellent game,” Macione said. “The aggressiveness that Hannah is playing with, coming out of the goal (to steal the ball), those are big chances to take in a high-stakes game like this. But Hannah’s confidence has improved so much.

“She has come up clutch for us when we needed her the most. I can’t say enough good things about her. She’s come so far, so far.”

n.griffen@theday.com