SOUTH BEND — Kyle McCarthy still laughs about those 2-on-1 backyard football games, in which younger brother Dan always found himself on the short end of the arithmetic.

“It would always be one of my friends and me against him,” the former Notre Dame safety recalled. “And for whatever reason, Danny decided that was fair.

“He would get the ball, and we’d just whoop up on him, and he’d get up and keep going every time.”

And Kyle McCarthy is convinced that player is still inside the No. 15 Notre Dame jersey assigned to his younger brother for a fifth and final season this fall.

“He’s tough as nails, and I’d kind of like to take credit for that,” the elder McCarthy said with a chuckle. “But after everything that’s happened to him, I’m expecting big things for him this season. And I know that’s what he’s expecting from himself, too.”

Dan — the more highly recruited of the McCarthy brothers, the former Ohio Gatorade Player of the Year in high school, the second team prep-All-American (USA Today) — has almost as long of an injury report than statistical highlights through his first four collegiate seasons.

It started with a serious neck injury during a playoff run his senior season at Youngstown Cardinal Mooney High. Dan, a quarterback/safety, for the perennial Ohio prep power, was injured during helmet-to-helmet contact while playing defense.

“It was a broken vertebra and a corrupt disc,” Dan said. “So they had to repair that with fusion.”

“I was in South Bend when it happened, and I got this phone call,” Kyle said. “At that time, whether Dan was going to play football or not was the last thing on my mind and on our family’s mind. We just wanted him to get healthy any way he could.

“When it got to the point where football did become an option, Danny took it upon himself to make it clear he wanted to come back and fulfill his dream to play football at Notre Dame.”

It sure hasn’t played out like a dream.

Four years in, the injuries continue to amass and Dan’s career tackle total stands at 16. Kyle, meanwhile, almost had that many in a single game against Pitt in 2008 (15).

That same season, the elder McCarthy became the first defensive back in ND history to college 100 tackles or more (110). In 2009, he did it again (101) before embarking on a pro football career, first with the Denver Broncos, then Kansas City.

“I’m healthy now,” Dan McCarthy offered of his situation. “It’s what you work for. I’m happy and blessed to have this opportunity, and hopefully I’ll make the most of it.”

A shoulder injury to teammate Austin Collinsworth, and subsequent surgery that will keep him out until at least late October, widened the opportunity for the younger McCarthy. Irish head coach Brian Kelly likes to play three safeties fairly regularly, and Dan is angling for that opening.

Then again, safety is perhaps the deepest position group on the team, with 11 scholarship players, not including Collinsworth. Seniors Zeke Motta and Jamoris Slaughter are the projected starters.

McCarthy looks to emerge from a group that includes sophomore Eilar Hardy, former walk-on and Bengal Bouts boxing champion Chris Salvi, true freshman Elijah Shumate and 20-year-old freshman Chris Badger, recently returned from his Mormon Mission.

“Just whatever I can do to help out,” Dan said of his desired role. “Whenever the coach calls upon you, you have to be ready at that moment.”

Toughness certainly won’t be an issue. In addition to Kyle’s warped sense of fair play in the family football face-offs, the culture at Cardinal Mooney infused that quality in Dan as well.