When Nick Schroeder's 3-point shot slid smoothly through the net midway through the second quarter Monday night, it gave the Brighton High School boys basketball team a 19-16 lead over Huron.

That lead was short-lived.

And the Bulldogs wouldn't make another shot from the floor for the next 16 minutes of play, by which time the Class A district host River Rats had their 55-37 opening-round win all but wrapped up.

"We knew we were playing well enough defensively to make (Brighton) take tough shots -- and they were hitting them," Huron coach Waleed Samaha said. "In the second half, we wanted to take away those shots they were getting."

Huron cranked up its defense a notch and held Brighton -- which averaged 51.8 points while rolling to an 18-2 regular season record -- without a basket from 4:52 left in the second quarter until 5:01 remained in the fourth.

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Brighton senior point guard Jackson Armstrong keyed the Bulldogs' one big offensive push, a 9-0 run in the second quarter that could have been more significant had they not missed the front-end of three one-and-one free-throw opportunities.

But Huron responded with a 15-3 run of its own to lead 31-22 at halftime, when the River Rats schemed a way to make sure Armstrong wouldn't hurt them again.

Junior guard A.J. Mathew was given the assignment for most of the second half, holding Armstrong to a single point.

"A.J. was just outstanding," Samaha said. "On a night when he struggled a little bit offensively, he found it in himself to pick it up defensively. That's the culture of our team right now."

Mathew and Dante Williams led the River Rats with 12 points apiece while Jalen Bouma added 10 and Mike Lewis nine.

Mathew scored seven of those points in the third quarter, including a 3-pointer that gave the River Rats their biggest lead to that point, 43-26, with 2:43 left.

Brighton, led by Schroeder's 13 points, never got back within 15 points.

Huron hosts South Lyon in Wednesday's 7:30 p.m. semifinal.