Rangers versus Astros. Three roaring crowds, first place on the line, September baseball the way it has never been in the Lone Star State. On Labor Day afternoon, in front of a packed house at Arlington’s Globe Life Field, arguably the most important regular-season series ever played in Texas got off to a fabulous start with a back-and-forth game that was tied 5–5 entering the seventh inning.

Pretty much nothing in sports is as much fun as pennant-race baseball, in which entire seasons seemingly ride on every pitch. We’ve watched it for years in other places and times, like those seasons when the Boston Red Sox and the New York Yankees unleash a century of spite on each other. It’s beautiful, exhausting, and finally ours.

This has been the summer some of us baseball-loving types have dreamed of, with the Rangers spending about 150 days atop the American League West and the mighty Astros looking vulnerable in their quest for a seventh straight playoff appearance and back-to-back World Series wins.

This three-game series began with the two Texas teams in a virtual tie for second place in their division and one game behind the Seattle Mariners. Neither was playing particularly well, the Astros having just been swept by the Yankees at home and the Rangers having lost twelve of sixteen to surrender the last of the lead they’d held over the division for most of the season.

But in those first six innings on Monday, the teams delivered like two clubs playing for their postseason lives. The Rangers led 3–0. The Astros tied it. The Rangers led 4–3. The Astros led 5–4. The Rangers tied it again.

This was on point for a magical season in which the two teams are on track to draw nearly five million total fans to their ballparks this year. At one point, as the Rangers roared out of the gate with a 40–20 record and were scoring more than six runs per game, they were breathlessly compared to the 1927 Yankees, the team of Babe Ruth and Lou Gehrig generally considered the best of all time.

The Astros? After winning more than one hundred games in four of the previous five full seasons and going to the World Series four times and winning it twice, this season’s version fell back to earth amid an array of injuries and slumps. The Yankees had outscored them 17–7 in the three losses at Minute Maid Park heading into this series with the Rangers.

That’s how things were lined up when Houston designated hitter Yordan Álvarez opened the seventh inning of that 5–5 Labor Day game by drawing a walk from Rangers reliever Josh Sborz. Alex Bregman and Kyle Tucker followed with singles to load the bases.

The Rangers couldn’t have known it at the time, but this was when the series—and maybe their season—was about to come undone. For all the spending the team had done over the last two offseasons and all the club’s smart moves, such as hiring three-time World Series winner Bruce Bochy as manager, the Rangers front office had been unable to repair a wretched bullpen.

General manager Chris Young had picked up a pair of relievers—once-dominant Aroldis Chapman and Chris Stratton—at the trade deadline, but the acquisitions had failed to move the needle. Now, in the most important game of the season, Bochy didn’t even have them after a difficult weekend series against the Minnesota Twins. In the seventh inning of a tied game, the manager knew what no one else did: he was going to ride Sborz no matter what, and if it meant taking a beating to set his team up for the final two games, so be it.

Sborz walked José Abreu to force in a run. Shortstop Corey Seager muffed a ground ball to allow two more. A three-run homer by rookie Yainer Diaz made it 11–5.

We won’t know for weeks the full impact of that awful inning on the Rangers. We won’t know if it put the Astros back on track for a third championship, or if the Rangers can right themselves enough to grab the American League’s third and final wild card playoff berth. “It’s going to take one swing of the bat or one big play,” Seager told reporters. “That’s just the situation we are in right now. Everything is amplified right now because of where we are in the season. We’ve got to be able to handle the big moment.”

What we know for sure is that the Astros dominated the Rangers in a way few contending baseball teams have ever dominated another contending team, closing out Monday’s game to win by the lopsided score of 13–6, then following that up with 14–1 and 12–3 wins on Tuesday and Wednesday. Bochy’s bullpen was so stressed that backup catcher Austin Hedges was summoned to pitch the ninth inning in two of this week’s games.

The Astros hit sixteen home runs over the three-game series and became just the fourth team to hit at least five homers in three straight games, according to MLB.com’s Sarah Langs. They’re also the first team to have fifty hits and sixteen home runs in a three-game series.

“I think every team responds differently to adversity,” Texas ace Max Scherzer said, “and every player responds to adversity in a different way. . . . Everybody can look in the mirror and sit there and say, ‘I wish I could do something better.’ That’s what it takes at this level. The line between good and great, it’s so small, and little things beat you every single time out. Everybody’s got to just do their job just a little bit better.”

Astros second baseman José Altuve homered five times in the series, and on Tuesday he became the first player since 1894 to hit four home runs in four consecutive innings (spread across two games). “He goes, we go,” utility man Mauricio Dubón said. “That’s how we’ve been. Every time he does it, we’re not surprised, really, but at the same time, it’s unreal what he does.” Altuve’s two stints on the injured list are part of what has slowed the Astros this season, and with Tuesday’s romp factored in, he’s been hitting .377, with nine home runs, since his return on July 26.

Álvarez also missed time this year, and outfielder Michael Brantley was sidelined almost five months while recovering from shoulder surgery. Álvarez homered in the first inning on Wednesday, and Brantley added one in the second. The Astros look whole again. “We said before we got here, ‘It’s time to go,’ ” Astros ace Justin Verlander said. “That was a tough series against New York. And we’ve got to show up. And it’s not quite playoff baseball, but it’s time to bring that energy and focus. And you see what these guys are capable of when they do that.”

Against Houston, the Rangers couldn’t even cash their biggest trade deadline ticket, Scherzer, who was pummeled for seven runs in three innings on Wednesday in a matchup against Verlander, his rival and former teammate. The two began the season with the New York Mets and have (somewhat) played down reports that they didn’t get along. Verlander acknowledged some tension, but he said that was mostly felt years ago, during their time together as young stars with the Detroit Tigers. For his part, Verlander dominated on Wednesday, allowing one earned run in seven innings. After the game, Scherzer said he was dealing with “an ailment”—likely a recurrence of his reported Friday “forearm tightness,” one of the most frightening phrases a pitcher can utter.

Anyway, the Astros on Tuesday took over sole possession of first place in the AL West and now lead the Seattle Mariners by two games. Meanwhile, the Rangers have seen their season-long lead morph into a four-game deficit. Even more troubling, they’re a half game behind the Toronto Blue Jays in the race for the AL’s sixth and final wild card playoff berth. “In 38 years working this market, which covers a lot of bad baseball, I don’t believe I’ve seen anything as inept with stakes as high,” Dallas Morning News columnist Kevin Sherrington wrote.

The Astros appear to have an easier path to the playoffs than either the Rangers or Mariners. On Friday, they’ll begin a stretch of nine straight games against teams with losing records as the Rangers play three against baseball’s worst team, the Oakland Athletics, before a seven-game road trip against two contenders, Toronto and Cleveland. Their season ends with four games in Seattle.

This week’s three games drew 109,276 fans to Arlington’s Globe Life Field, with a significant portion of Astros fans showing up. Meanwhile, in Houston, six years of dominance on the field have paid off at the gate, with the Astros on their way to drawing three million fans for the first time since 2007. Reacquiring Verlander at the trade deadline after the pitcher departed via free agency last offseason energized Astros fans at a point in the season when simply making the playoffs looked like it’d be a challenge. Now the team is on top of the division and appears to be peaking at just the right time.

“If there’s one person that gets impressed by what this team can do, it’s me because I’m new here,” said Abreu, a free agent signee last offseason. “I think that this organization, these guys, when the lights are shining bright, they know how to handle things, they know how to do things well. I’m just very grateful to be part of this as well.”