Deep River — Jake Kruszewski had a simple, primal reason for wanting to start playing football when he was younger.

“I want to hit kids,” Kruszewski said about his motivation. “That’s what it came down to.”

Kruszewski is still hitting kids as a starting cornerback/running back for the Valley Regional/Old Lyme co-op. He’s one of its leading tacklers and a senior co-captain.

The sixth-seeded Warriors play at No. 3 Rocky Hill in Tuesday’s CIAC Class S quarterfinals (6:30 p.m.)

“He might be one of the toughest kids you’ll ever want to meet,” Valley/OL head coach Tim King said. “Pound-for-pound, he may be one of the top five strongest kids we’ve got.”

There’s one big thing that stands out right away about Kruszewski — his size. He’s 5-foot-6 and 155 pounds.

Bigger isn’t necessarily better in football, but it sure helps with all the collisions. It’s also an unwritten job requirement at the college and pro level.

Size is why former linebacker Sam Mills (5-foot-9) was a walk-on at Montclair State and was undrafted after college. It forced him to go to the USFL before catching on with the New Orleans Saints and becoming a multiple All-Pro pick.

Size is why Russell Wilson, considered too small at 5-foot-11, was a third-round pick (75th overall in the 2012 NFL Draft) despite his arm strength and accuracy, and why Ryan Tannehill, Brandon Weeden, Brock Osweiler were all drafted ahead of him.

“My dad (Todd) always told met that heart wins over everything,” Kruszewski said. “As long as you’ve got a big heart, nothing can stop you. Size doesn’t matter. That’s always what I thought. And I always played like I was 6-4. I didn’t care.”

Even King, who has never had to worry about leg room on a plane, had his reservations when Kruszewski came out for the team as a freshman.

“He’s kind of changed my attitude toward that type of thinking,” King said. “When he came in, we had some pretty good players at that point in time. He was a freshman when we won a state championship (2014). We had some pretty good corners.

“The very next year, he was a starting corner and pretty darn good. … He really has changed (my mindset) because he can play for a little guy.”

Kruszewski said, “At that point of time (freshman year), I still thought I was going to grow. … (When) I got varsity time and started making plays, they started playing me more, and I realized I had a good opportunity here. It didn’t really matter how tall I was, how big I was.”

Kruszewski has a team-leading 25 solo tackles for the Warriors (9-1). He’s third in overall tackles (56), is tied for the team lead in interceptions (five), and has forced a fumble and recovered another.

“Small as he is, he’s our press coverage (bump-and-run) corner,” King said. “That kid has heart and is tough. And talk about setting the edge (a position usually reserved for defensive ends or outside linebackers). You’d think that he’d be kind of reluctant to set the edge (being responsible for making sure the runner can’t get outside) and come up on kids. He doesn’t care how big you are.”

Kruszewski also has 43 carries for 322 yards and five touchdowns, caught six passes for 87 yards and a touchdown, and returned eight kickoffs for 158 yards.

It should be obvious by now which side of the ball Kruszewski prefers to play.

“O-ooo. I like defense better,” Kruszewski said. “I like hitting people. For sure (defense).”

n.griffen@theday.com