MIAMI GARDENS, Fla. — The fact Georgia and Michigan football “mirror” one another in many ways has become a prevailing storyline of the Orange Bowl CFP Semifinal.

The No. 3-ranked Bulldogs (12-1) and No. 2-ranked Wolverines (12-1) kick off at 7:30 p.m. from Hard Rock Stadium with Kirby Smart and Jim Harbaugh on opposite sidelines.

Smart, a 46-year-old from Bainbridge, Ga., wouldn’t seem to have much in common with the 58-year-old Harbaugh, who was born in Toledo, Ohio, but moved frequently before graduating from Palo Alto High School in California.

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But both Smart and Harbaugh grew up the sons of football coaches who went on to coach at their alma maters: Smart an All-SEC safety at Georgia, and Harbaugh, a 1986 All-American and third-place finisher in the Heisman Trophy race.

Another interesting twist, both share the same birthday (Dec. 23).

A not so fascinating — or surprising, for that matter, similarity — is the affinity Smart and Harbaugh have for hard-nosed football on offense and defense.

Most every football coach talks that game, but Smart and Harbaugh live it, to the extent both have been labeled as being “too conservative” on offense at times.

Michigan ranks 10th in the nation with 223 yards rushing per game, while Georgia ranks 30th at 194.9 per contest.

There are 101 teams (out of 130) that have a higher percentage of pass plays to run plays; the Wolverines only 114th in pass/run ratio and the Bulldogs 102nd.

Harbaugh pointed to the mere physicality a good run game can bring, and though he didn’t mention it, the Wolverines ability to rush effectively has played a role in UM allowing fewer negative plays than any Power 5 team in the nation.

“Just always striving to be really good at that at the phase of running the football, and on defense being able to run and hit and wrap up and make tackles and pursue,” Harbaugh said on Thursday, after DawgNation asked the question and the coach’s mutual press conference.

“It’s a physical sport. Yeah, you always strive to be as good in that area as you can, and you want to be good in the kicking game just like you want to be good in the protection phases, you want to be good in the throw game. You’re striving to get really good in all those phases.”

Smart was more direct and also went down the path of physicality.

“To me being physical is part of the sport,” Smart said. “If you’re not going to be physical you’re probably going to struggle. That starts with the line of scrimmage. There comes a point in almost every game where you have to be able to run the ball, whether that’s four-minute, end-of-game stuff or that’s short yardage. There has to be a commitment to moving forward and putting your hat on people.

“Nowadays it’s probably done a lot more on the perimeter in terms of there are hats on hats on the perimeter now more than ever, and every play has multiple plays to it, and you’re playing a defensive line block technique, you’re playing it out on the perimeter. You’re blocking somebody at receiver more now than ever because there’s a perimeter screen attached to every play. I think that’s made the premium on being physical more.”

Smart made it clear he appreciates how Harbaugh approaches the game and looks forward to it.

“We’ve got a lot of respect for Coach Harbaugh and his team,” Smart said. “They’ve always played a physical brand of football, and our guys are looking forward to that opportunity to go out and play.”