In one way, at least, this World Series is unique in baseball history: We have never had a matchup of two teams that were once division rivals. This is only possible, of course, because the Astros are one of two teams -- along with the Milwaukee Brewers -- to switch leagues. The Astros were in the National League until 2013. They are the only team in baseball history to have won American and National League pennants.
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And there was a brief time, not so long ago, when the Los Angeles Dodgers were their most heated rival. In the 1970s -- like the '60s and '50s -- the Dodgers were a dominant team in the National League. The perpetual excellence of the Dodgers drove the rest of the league mad; they were good more or less every year (from 1950 to '79, the Dodgers posted a .567 winning percentage, far and away the best in the National League).
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Yes, the Cincinnati Reds built a superteam, the Big Red Machine, that, for a moment -- 1975 and '76 -- vanquished Los Angeles and everybody else.
But the Dodgers promptly took back the league, winning pennants in 1977 and '78 behind a team of stars, led by their iron infield of Steve Garvey, Davey Lopes, Bill Russell and Ron Cey. Manager Tommy Lasorda wrote those four into the lineup pretty much every day and, along with a strong rotation and good-hitting outfielders like Dusty Baker and Reggie Smith, the Dodgers just kept on winning.
The Houston Astros, on the other hand, had their own story … a story of striving and, inevitably, falling short. They tried countless plans in the late 1960s and throughout the '70s, only to watch them fizzle. But in 1979, the Astros had their best record to that point -- 89 wins -- and for the first time in their history, actually finished ahead of the Los Angeles Dodgers. These were heady days for Houston baseball. They were so close.
And the Astros went for broke. Before the 1980 season, they signed fireballer Nolan Ryan to join fireballer J.R. Richard, giving the Astros two of the hardest-throwing pitchers in baseball history. They also signed two-time MVP Joe Morgan.

"I came here to win another championship," Morgan said.
For the next two seasons -- 1980 and 1981 -- the Astros and Dodgers went at it.
The 1980 Astros had an emotionally draining season. That was the year that Richard -- one of the best pitchers of the 1970s -- collapsed on the field before a game and almost died of a stroke. Somehow, though, the Astros kept winning and were in position to wrap up the division title on the last weekend. They led the Dodgers by three games with three games to play. Unfortunately for them, they would have to actually beat the Dodgers in Los Angeles to clinch the title, but they were confident about that.
"We can buy champagne in L.A. just as easily as we can buy it here," Enos Cabell said as the team headed to Los Angeles.
The Dodgers didn't have much use for that statement or the Astros in general. They knew they had to win four straight to take it away from Houston -- three games to end the season and then a one-game tiebreaker.
"If we win the first one," Lasorda told the press, "then we can win the second one."
They won the first one in extra innings on Joe Ferguson's walk-off home run against Ken Forsch. Then they won the second one, 2-1, on Steve Garvey's home run off a Ryan fastball. It was the eighth consecutive time that Ryan had lost to the Dodgers.
"Pressure is what the game of baseball is all about," Garvey said.
Then came the third game and another wild Dodgers victory, this one a 4-3 win coming on Cey's two-run homer in the eighth inning.
"Dodger baseball has always been like this," Cey crowed after the game. "Every game, whether we lose it in a heartbreaker or win it, seems to be exciting like this. I guess it's the so-called Hollywood atmosphere, but no one could write a script on a day-to-day basis like this."
"I've never seen anything like this in my life," Lasorda said.

That forced the one-game playoff … and at this point, everyone knew that the Dodgers would win because they were the Dodgers. Except, for the first time in Astros history, the script flipped. This time, the Astros got dominant pitching from knuckleballer Joe Niekro and three key hits from Art Howe and rolled to a 7-1 victory in Dodger Stadium, a den of nightmares for the Astros through the years. The game was briefly stopped and the Astros were pulled off the field in the fourth inning when fans kept throwing stuff on the field.
"It was very humiliating when we lost the first three," Astros right fielder Terry Puhl said. "It would have killed me to lose this one."
"Finally," Morgan said, "it's ours."

The Astros would go on to lose a tight, tough National League Championship Series to Philadelphia. And then, in 1981, the Astros and Dodgers would meet again, this time in a rollicking five-game Division Series made necessary by the '81 player's strike. This series, if anything, was even wilder than the '80 finish.
• 1981: The last time the Dodgers and Astros met in the postseason
The Astros won the first game behind the overpowering pitching of Ryan, who figured out how to beat the Dodgers in 1981. He threw a no-hitter against them during this season. And in Game 1, Ryan allowed just two hits (yes, one of them was a Garvey home run -- Garvey seemed to have Ryan's number in those days).

The Astros also won Game 2. The game was scoreless going into the bottom of the 11th when Houston loaded the bases. The Astros' pinch-hitter Denny Walling -- he was often called "pinch-hitting specialist Denny Walling" -- faced Tom Niedenfuer.
And Walling lined a ball into the right-field gap to win it.

"That's his forte!" Astros manager Bill Virdon said. "He's a real competitor."
And here were the Astros again, on the brink of finishing off the Dodgers as the series switched back to Dodger Stadium. Los Angeles needed to win three in a row to move on. Lasorda made more comments about needing to win one at a time.
And the Dodgers breezed to victory in Game 3, setting up a classic battle between Dodgers rookie sensation Fernando Valenzuela and Houston's veteran Vern Ruhle. It was Ruhle who dominated at first; he had a perfect game going with two outs in the fifth inning. He then threw a fastball to Pedro Guerrero -- "It was a good pitch, I'd throw it again," Ruhle would say -- and Guerrero turned on it and mashed it into the left-field seats.

"As soon as I hit it, I knew it was gone," Guerrero said.
The Dodgers added another run and Valenzuela pitched beautifully to force a Game 5 -- the second straight year that Houston and Los Angeles would essentially have a one-game playoff for everything. The Astros felt pretty good coming in because Ryan would be their starter. The Dodgers went with Jerry Reuss.
This time around, it was the Dodgers who rolled, scoring three runs off Ryan in the sixth inning. One key play in the inning was Walling losing a popup in the sun. "You can't catch what you can't see," Walling said with a shrug.
Another was Rick Monday ripping a single on a Ryan fastball after just missing and fouling off a similar fastball.
"When he threw me a good fastball, and I fouled it off, I wanted to call time to ask [California Governor] Jerry Brown to send in the National Guard to get one more pitch like that," Monday said.
Reuss was masterful, allowing just five singles and three walks in the game. The Astros only managed to get one runner to third in the entire game.
"Call it an ego trip or call it a sense of place and time," Reuss said. "But when I pitch, I feel like the mound belongs to me. When I got those three runs, I knew I'd control my side of things."

The game ended ignominiously for the Astros with pinch-hitter Dave Roberts -- not the Dave Roberts who manages the Dodgers -- striking out and then walking back to the dugout even though the ball had gotten past Dodgers catcher Mike Scioscia. Fans had begun running on the field when Scioscia got to the ball and threw to first to finish the game.
"When we came back from Houston, I knew we'd win all three games," Lasorda said. "These guys don't know what it means to quit. I knew they'd do it."
Those Dodgers went on to win the World Series.

The Astros and Dodgers were together in the National League West for another dozen seasons, but they never really went head-to-head again. Then Houston moved into a different division, then a different league, but us old-timers still remember the time when the Astros and Dodgers were at each other's throats. Not one of the Dodgers or Astros players -- not even Chase Utley or Carlos Beltran -- is old enough to remember, but it's still there, in the background. This is not the first time that Houston fans will be chanting, "Beat L.A.," and not the first time that Dodgers fans will be nervously dealing with the Astros.