HOUSTON — Fifty years ago, Dusty Baker put the minor leagues behind him for good. Baker, now the manager of the Houston Astros, spent the summer of 1971 playing for the Class AAA Richmond Braves. He remembers whose arrival sent him there from Atlanta: Tony La Russa, now the manager of the Chicago White Sox.

“I know they sent me back to Triple-A and kept him. That’s what I remember,” Baker said this week, before the start of an American League division series between his Astros and La Russa’s White Sox. “I think he was five years older than me, and they didn’t want me sitting on the bench.”

La Russa is 77 now, and Baker is 72. The rest of the story, alas, does not add up: Baker had been sent to the minors in May 1971 when the Braves promoted Darrell Evans. They purchased La Russa’s contract from Oakland in August.

“Actually, Hank Aaron was the one that sent me back,” Baker clarified, meaning that Aaron was blocking him from getting regular playing time. In any case, La Russa and Baker played just one game together, at the very end of the 1971 season. La Russa was nearly done as a player, and Baker would last 15 more seasons.

By the end, when Baker was with the Athletics in 1986, La Russa was his manager.

“I hate to say we were teammates because it means I was a player like he was a player — he was a really good player. I was not,” La Russa said. “But we were teammates, and I have known him quite a bit over the years. The only problem we’ve ever had is when we’re in the same division. Other than that, we’ve never had problems.”

Of course, they were in the same division for a long time: eight years in the National League Central between 2003 and 2011, when La Russa managed the St. Louis Cardinals and Baker guided the Chicago Cubs and the Cincinnati Reds.

Their rivalry simmered then, with friction from hit batters, bench-clearing brawls, All-Star Game snubs and managerial mind games. That intensity is reflected in their record against each other: an even 104-104 in the regular season.

This is the second time a La Russa team has met a Baker team in the playoffs; the other was a five-game victory for Baker’s San Francisco Giants over La Russa’s Cardinals in the 2002 N.L. Championship Series. It remains Baker's only pennant in his 24 seasons as a manager, and his team lost the World Series in seven games to the Angels.

La Russa managed for 33 seasons without a break, from 1979 through 2011, with the White Sox, the A’s and the Cardinals. He won six pennants, three championships and a spot in the Hall of Fame, then returned to Chicago this season after a 10-year hiatus from the dugout, eager to fit in with a team on the rise.

“The first conversation I had with him in the off-season, right when he was hired, I was expecting Tony La Russa, Hall of Fame manager, to be very strict, to be very like: ‘I’m in charge. This is what we’re going to do,’” said Lucas Giolito, who will start Game 2 on Friday. “And I was very surprised when, in our first conversation, he told me that: ‘I’m coming over. This is your guys’ team, and I’m going to work every day to earn your respect starting in Day 1 of spring training.’ And he’s done that.”

Jerry Reinsdorf, the owner of the White Sox, had always regretted La Russa’s departure in 1986, when General Manager Ken Harrelson fired him. The White Sox are the only team La Russa has managed that has not won the World Series with him.

“This club has inspired me,” La Russa said on the field during batting practice before Thursday’s Game 1 in Houston, after praising the team’s attitude in the interview room. “It’s a very spirited bunch. In years past, we’ve had some clubs that had something like this — a vocal spirit — but this is a real spirited bunch all the time, from the minute you walk in the clubhouse to their pregame, during the game, after the game.”

Like La Russa, who inherited a playoff team from the previous manager, Rick Renteria, Baker took over a strong Astros team before last season. The Astros were coming off an A.L. pennant, but they fired Manager A.J. Hinch after revelations of illegal sign stealing during their 2017 title run.

With no connection to the scandal and a knack for bonding with players, Baker fit well for a team in crisis that would also be missing two elite starters: Gerrit Cole, who had signed with the Yankees, and Justin Verlander, who had just one start before sustaining an elbow injury that also cost him the 2021 season. Framber Valdez and Luis Garcia, among others, have capably taken their place.

“The confidence he instills in you and the understanding of his players — myself as a Latino as well — he helps you understand that sometimes you’re going to achieve things in the game, sometimes you’re going to fail,” Valdez, who is from the Dominican Republic, said about Baker through a translator. “But he doesn’t let you get too up or too down, and he transmits that positive energy at all times.”

The Astros struggled for much of the 60-game season in 2020, but recovered well enough to reach the A.L.C.S. in an expanded playoff format. Now they are coming off a West division title and setting Baker up to chase the championship that has eluded him as a manager.

“You keep knocking on the door, man,” Baker said. “If you don’t knock on the door, you don’t have a chance. The way I look at it, Thomas Edison, he tried a thousand times before he discovered the light bulb and electricity.”

Baker ranks 12th on the career list for wins by a manager, trailing 10 Hall of Famers and Bruce Bochy, who retired in 2019 after winning three titles with the Giants. A World Series victory with the Astros would seemingly assure Baker of a plaque near La Russa’s in Cooperstown, but to his peers, he is already worthy.

“One manager’s in the Hall of Fame and the other’s on his way there,” said Terry Collins, 72, a former Mets manager. “They’ve seen everything you could possibly see.”

Including the sight of the other guy in the opposite dugout — hundreds of times, but rarely more important than now.