The 6-foot-9, 275-pound senior - a Notre Dame recruit and arguably the best high school lineman in the area - wears a yellow wristband that has the words Power Through Pain. They also appear on his Twitter page, @BigGlinch74.
That motto, ironically, speaks a lot to McGlinchey's off-field, softer side.
His girlfriend, a classmate at Penn Charter, suffers from a chronic pain syndrome called reflex neurovascular dystrophy (RND). Power Through Pain is a motivational slogan for RND patients. McGlinchey touts it because of his girlfriend's battle, and because it fits his mentality.
McGlinchey is very much a family guy, too, and that factored into his college decision. And what a football family it is.
Matt Ryan, the Atlanta Falcons quarterback and former Penn Charter and Boston College star, is his first cousin; their mothers (née Loughery) are sisters.
McGlinchey's uncle John Loughery also was a quarterback for Penn Charter (Class of 1978) and Boston College. John Loughery's son, John, is another former Quakers quarterback and a freshman at Division I-AA Elon.
McGlinchey thinks he gets his height - he is listed at 6-9 but says he's "probably 6-8 and some change" - from the Loughery side of the family. He says his father, also Mike, is about 5-11; his mother, Janet, about 5-8.
He and his dad made an unofficial visit to Notre Dame in March, driving from their Warrington home to South Bend and planning to continue on to visit Wisconsin.
By the time McGlinchey got to Notre Dame, three offensive line recruits had committed to the Irish, including two in the past day, and coaches told him that they would take only one or two more and that another one was set to visit.
Despite that, and despite McGlinchey's being a longtime Notre Dame fan, he left the campus without accepting the scholarship offer. Before he could commit, he had to talk to his mother, his Uncle John, and Humble.
The McGlincheys went to Sunday Mass, shopped in the bookstore, and got in their car, heading toward Wisconsin. The younger McGlinchey got on the phone.
"I knew I wanted to go there, but I didn't know if it was actually going to be a reality and possibility for me," McGlinchey said. "I was a little nervous about how far it is from home. I was a little nervous about if I was actually going to be OK there. I knew it was my dream school forever. I just needed to get a couple of the logistics out of it.
"That was one of the things I had to call my mom about - see if she was OK with it. And she said, 'Mike, we're going to make it work, and we'll be out there and we're going to support you in anything you need to do.'"
McGlinchey had his father pull into a service-road gas station. He called Irish offensive line coach Harry Hiestand, his recruiter, to give his commitment, and also talked to head coach Brian Kelly. The McGlincheys returned to South Bend and chatted more with the coaches.
They never went to Wisconsin.
Notre Dame did add a fifth offensive line recruit. All five are between 6-5 and 6-9.
McGlinchey, also a defensive end for the Quakers, previously visited Maryland, Duke, Virginia, Boston College, Temple, and Penn State.
Some firm Boston College roots obviously run through the family, and famed graduate Ryan did advise McGlinchey during recruiting. Still bleeding B.C. maroon and gold, still wary of one of the Eagles' rivals, Ryan stressed one point.
"He was always saying, 'Don't go to Notre Dame. Every other school is OK except for Notre Dame,' " said McGlinchey, who at 17 is 10 years younger than Ryan. "He was just kidding. He just told me to have fun with it and find the place that's right for me."
And when McGlinchey found that place, what did Ryan say?
"Congratulations," McGlinchey said. "He was really excited. He's family. He's going to be supportive, no matter what."
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