Georgia, the defensive mammoth, and Alabama, the perennial juggernaut, seemed to be on a collision course to the top of college football all season.

They got a shot at each other in the Southeastern Conference championship in December — a game in which the Bulldogs barely resembled the behemoth they’d been from their first game. On Friday, each team romped past its College Football Playoff semifinal opponent, earning the chance to meet again in the game for the national crown in Indianapolis on Jan 10 — if the game is not disrupted by the coronavirus pandemic.

Alabama (13-1), which has won six national titles under Nick Saban (he took over the team in 2007), advanced to its sixth national championship game since 2015. Georgia (13-1), a program that has come close but has not won a national championship since 1980, advanced to its second national title game in five years (the Bulldogs lost to Alabama in overtime in 2018).

Alabama, after pummeling Ohio State in January to cap one of the most dominant seasons in college football history, entered the 2021 season with the rest of the nation in its wake.

Living up to last season’s output appeared unlikely, as the Crimson Tide — which lost a handful of players to the 2021 N.F.L. draft, including their 2020 Heisman Trophy winner, DeVonta Smith — barely edged out Florida in their SEC opener and lost to Texas A&M less than a month later.

Georgia, which entered 2021 with the country’s top-rated recruiting class, according to 247Sports, took over the No. 1 spot as it rolled through its schedule and went unbeaten in conference play.

And Alabama, despite its inconsistencies, remained a top-five team heading into its regular-season finale against Auburn. Saban, stern as ever, admonished his fan base’s criticisms of his team’s imperfections ahead of the Iron Bowl in late November.

“When I came here, everybody was happy to win a game,” Saban said on his radio show. “Now we’re not happy to win a game anymore.”

A week after their Iron Bowl win, though offensively stagnant in the game, the Crimson Tide smashed the nation’s best defense, amassing over 500 yards of total offense against a Georgia team that was only allowing about 250 yards per game. Before surrendering 41 points to Alabama, the Bulldogs had given up more than 13 points in a game only once this season.

The loss dropped Georgia Coach Kirby Smart, once an assistant coach on Saban’s Alabama staff, to 0-4 against his former boss.

Afterward, Smart told reporters that the embarrassing loss after an undefeated season did little damage to the Bulldogs’ psyche.

“What it did was reinvigorated our energy,” Smart said. “It re-centers you.”

That was apparent in Georgia’s 34-11 thrashing of No. 2 Michigan in the Orange Bowl, a physical game in which the Bulldogs’ defensive unit was nearly perfect.

“We knew we were better than what we showed last game,” quarterback Stetson Bennett said during the Orange Bowl’s postgame trophy ceremony.

The Bulldogs will have a chance to avenge a poor performance at the line of scrimmage where, uncharacteristically, they were bullied in the SEC championship game. While Georgia had no trouble getting pressure on opposing quarterbacks all season, the team failed to record a sack against Alabama a few weeks ago.

But the Bulldogs’ athletic defense, as motivated as it will be at Lucas Oil Stadium, will face Alabama’s offensive line at its best.

When the Crimson Tide struggled offensively during the regular season, it was often because of inconsistencies in the performance of its offensive line. Against Auburn, multiple breakdowns in pass protection allowed rushers to have easy avenues to bring down quarterback Bryce Young (he was sacked seven times).

In the conference title game, though, Young had the time and protection he needed to find receivers downfield and to make plays with his feet. And against the Bearcats in the Cotton Bowl, the Crimson Tide’s offensive line made way for running back Brian Robinson Jr. to rush for a career high as Alabama ran past Cincinnati to advance to the title game.

The championship matchup — if it is not derailed — will be the 72nd meeting between the teams. Alabama has won the last seven, and it will be the SEC’s seventh straight season sending at least one team to the national championship game.

College football, though certainly disrupted in numerous ways by the pandemic, made it through most of this season with few interruptions before bowl games started. But as the highly contagious Omicron variant led to a nationwide surge in cases, leagues shuffled their schedules, several bowl games were canceled and the College Football Playoff changed its health protocols in hopes of preserving the most important games.

Late Friday night, with seconds remaining before their win over Michigan was finalized, the Bulldogs looked ready to dump a cooler of cold liquid on the winning coach’s head.

Instead of taking part in the playful celebratory gesture, Smart could be seen speaking emphatically to his players, waving off their attempts at an early shower.

After one of their best seasons in years, a familiar foe awaits. The job isn’t finished yet.