East Lyme — East Lyme coach Phil Schneider was pointing out Tuesday night that he doesn't substitute on defense. The back four, Laura Agbayani, Sarah Christensen, Ellie McCoy and Erin Bauman have the floor, so to speak, along with senior goalie Maya Rose.

"They learn to play as five of them, the defenders and the goalie," Schneider said. "That way if they're in there and things don't go right, they have a chance to figure it out ... at halftime or right on the field.

"This is when you want to play as one."

Speaking of one ... the defense allowed just one goal in the second half as third-seeded East Lyme defeated No. 14 Mercy 11-9 in the opening round of the Class M girls' lacrosse state tournament. The Vikings (14-4) will face Eastern Connecticut Conference foe Fitch, the sixth seed, in the quarterfinals at 5 p.m. Thursday at East Lyme.

Fitch (13-4) defeated No. 11 Brookfield 17-5 in its tournament opener and will likely present another defensive test for East Lyme.

But as for this one, East Lyme held Mercy scoreless for the final 13 minutes, 24 seconds, rallying from a 9-8 deficit following a free position goal by Mercy's Mia Carbone.

The Vikings scored the game's final three goals, tying things at 9-9 on a free position by Julia Bates, taking the lead on a goal by Natale Taylor and getting an insurance goal from Bates on a free position with 3:56 to play, Bates' seventh goal of the game.

From there, it was a defensive stranglehold by East Lyme.

Mercy won the draw, but Bates forced a turnover, picking up a ground ball. Agbayani, an all-conference defender in soccer and lacrosse with the speed of a Class L state champion 4x800 runner, agitated Mercy into its next two turnovers, bringing the clock down to the 1:24 mark.

Mercy then turned the ball over three more times in the final minute.

Bates called the 5-foot-2 Agbayani "a powerhouse."

"Teams are really quick in transition," Bates said. "If the midfielders can't get back to help out right away, it's nice knowing they'll be able to hold down the fort."

"We're a really good unit," Agbayani said of the defense. "We have good communication. ... Being behind at halftime (8-7) just fueled us. At halftime we talked about make sure we're in the hole, making sure where the cutters were."

Agbayani said the entire team works on defense, right from the attackers who following a change of possession are assigned to redefend or blanket the opposing players trying to clear the ball, making it easier for the defense to intercede.

"That's the attackers. That's the middies. That's not just on the defense," Schneider said. "It's a strength of ours. ... We'd rather be better at holding the ball (down the stretch). There were a couple of unforced errors, too. Mercy's a good team."

East Lyme beat Mercy 12-7 on May 14 and got off to another strong start Tuesday, scoring 20 seconds into the game on a goal by Bates and again on a free position by Bates about a minute later.

The Vikings led by as many as three goals in the first half on a goal by Nancy Alden from Megan Bauman that made it 7-4. But the momentum belonged to Mercy, which scored four straight goals to end the half with a one-goal lead.

Taylor scored twice for East Lyme and Abby Moutain also had a goal. Carbone scored four times for Mercy.

Said Bates: "I think it helped (get better for the remainder of the tournament). We know now that we can make adjustments we need to make when we need to make them."

v.fulkerson@theday.com