Kirby Smart, a Georgia native and former Bulldogs player, will make his debut as a head coach at Georgia on Saturday. (John Bazemore/Associated Press)

With coaches zigzagging all over the vast American map as a rule of 21st-century college football life, the two biggest movers of the past offseason have gone to strange places. They’ve gone back home, where they’ll try to fuse an ounce of sentiment with a heap of skill and a ton of work.

That’s because Georgia decided it would see if it could do better than Mark Richt’s 15 seasons of winning 74 percent of the time (145-51), so that the Georgian former Bulldog free safety Kirby Smart could replace Richt, so that the Floridian former Miami quarterback Richt could move back to Miami.

“In December, I was given the opportunity of a lifetime, and I haven’t slowed down since,” said Smart, 40, who will try to take Georgia from very good to very, very good.

“Being back at my alma mater is huge for me; it’s kind of a good spot to finish my career,” said Richt, 56, who will try to take Miami from lost to good.

In the annual — or more-than-annual — volatility, Smart is the only non-interim head coach who will debut for a preseason top 25 team this Saturday , when No. 18 Georgia meets No. 22 North Carolina in Atlanta. Infamously, No. 23 Baylor will complete a grotesque offseason of losing its head coach, athletic director and president after the mishandling of sexual-assault cases involving players, and it will start again Friday night in Waco, Tex., against Northwestern State (La.) with interim coach Jim Grobe.

Mark Richt, first by Georgia last season after 15 years, is now the head coach at Miami, his alma mater. (Alan Diaz/Associated Press)

Grobe, in an achievement that soars beyond football and rivals great works of science, once coached Wake Forest to an ACC football title, won in a 9-6 bruiser over Georgia Tech in the 2006 conference title game.

In the eight years of coach Art Briles, Baylor fans did not know much 9-6.

Three of the seven coaches in the SEC East Division, including Smart and South Carolina’s Will Muschamp (formerly the top man at Florida), are new. So are four of the 14 in the ACC, and three of the seven in the Coastal Division, including Richt, Virginia Tech’s Justin Fuente and Virginia’s Bronco Mendenhall. Seven of the 14 Big Ten helmsmen will coach either for the first year or second, including debutants DJ Durkin of Maryland, Chris Ash of Rutgers, Lovie Smith of Illinois (that rarity who once head-coached in a Super Bowl) and Tracy Claeys of Minnesota, who already went 2-4 as an interim last fall. Still, the American thirst for ceaseless victory might find its best emblem in the compelling American Athletic Conference, a rising second-tier league where seven of the 12 coaches are in either Year 1 or 2, with only one beyond Year 4: that learned, ninth-year mainstay Ken Niumatalolo at Navy.

So much of it winds up interconnected. In mid-January 2005, Richt hired a new running backs coach from LSU to Georgia and said, in a statement, “We’re getting a high-energy coach with lots of enthusiasm who is also an outstanding recruiter.” The coach was Smart, and he stayed one season.

Further, Richt played at Miami for Howard Schnellenberger, whose offensive coordinator was Kim Helton, whose 44-year-old son, Clay Helton, coached Southern California as an interim in 2015. He went 5-4, shed the “interim” label and will debut for real — for very, very real — for the No. 20 Trojans on Saturday in Arlington, Tex., against No. 1 Alabama.

At Alabama, the head coach will begin his 10th season. It has gone better than average. As Nick Saban operates in an SEC West of uncommon stability — all seven coaches are on at least their fourth seasons — he also has exacerbated the usual national coaching tremors.

When Smart did leave Georgia after that one season, he did so because Saban lured him to the NFL’s Miami Dolphins. Saban then lured him to Tuscaloosa, where Smart spent eight years, four national championships and one further College Football Playoff berth as defensive coordinator. Thus did Saban’s prowess both elevate envy among peeved neighbors such as Georgia, but also the idea of Smart as someone who might know how to reach the rarest realms.

He will try it where he played and studied from 1995 to 1998, under Ray Goff and Jim Donnan, making football all-SEC and academic all-American. Things went from 6-6 in 1995 to 10-2 in 1997 to 9-3 in 1998, closing Smart’s career with a Peach Bowl win over Virginia during which a rattled freshman quarterback Quincy Carter said, “Kirby Smart came over to me and said, ‘Stick in there, we believe in you.’ ”

He told Georgia reporters then, “When I was growing up [in Bainbridge, Ga.], Georgia was good every year. My whole goal when I came here was to leave here with things back to like they were when I was young.” The calm, measured demand now would be for him to make them actually somewhat better than that.

By contrast, Richt came out of Boca Raton High School in the late 1970s to find a Miami pointing way upward. It would win the 1983-84 national championship, the year after Richt left, plus four more times up to 2001-02. Reaping from the rich three counties of football talent (Dade, Broward, Palm Beach) that still figure to help Richt, it would become the kind of place that did not feel so jazzed about 12 years without a 10-win season and nine without a bowl win, the situation now. In fact, Miami being Miami, it would treat such things with a rare level of inattention.

In the third game of the 1982 season, the senior Richt replaced the injured future Hall of Famer Jim Kelly. He would quarterback five games from there, throwing four touchdown passes and nine interceptions, getting booed in the Orange Bowl even in a 31-14 win over Mississippi State, worrying for his mother and sister in the stands. He would keep the job all the way until Miami prepared to visit Maryland in early November, when Schnellenberger suspended him for violating a dormitory rule. While his teammates defended him and Kim Helton criticized him, Richt would plead to media, including the Miami Herald, for some privacy for college athletes, and say, “Are we playing football or do we have a soap opera here?”

By now, he would know that all of life and college football is an enduring soap opera, and he would become Bobby Bowden’s offensive coordinator at loathed rival Florida State before heading to Georgia. Now, he goes back to Miami with fond memories of past brotherhood to start with an experienced quarterback (Brad Kaaya) and an opener on Saturday with Florida A&M, of which he said in his news conference on Tuesday, “I won’t have time to be nostalgic.”

He’ll be all the way back where he started — and started with Saban, the former Miami head coach who recruited Richt to Miami.

Of course, that was Lou Saban.