The last time our beat reporters in the American League West convened, the Mariners, Rangers and Astros were at the onset of the final month in a historically close race for the division title. And perhaps unsurprisingly, things haven’t changed in the standings in the three weeks since.

The Mariners, Astros and Rangers all entered their final off-day on Thursday within a half-game of each other. All three teams won Wednesday, but that’s the last time that’ll happen this year, as the Mariners spend this weekend at Arlington, then return home for three against Houston before playing four more against Texas.

Odds to reach postseason, per FanGraphs:
Astros: 90.8%
Mariners: 60.7%
Rangers: 64.6%

• Who holds postseason tiebreakers?

MLB.com’s Sarah Langs, with some help from the Elias Sports Bureau, put into context just how tight this finish is shaping up to be:

• Remaining schedules: Astros | Mariners | Rangers

A quick reminder of MLB's tiebreaker rules, if all three clubs were to finish with the same record after 162 games:

• If one team finishes with a winning head-to-head record vs. each of the other two teams, that team would be the AL West champion. As of now, that’s not the case. Texas leads Seattle, 5-1 (seven games remaining between these two), Seattle won the season series over Houston, 8-2 (with three games remaining), and Houston won the season series over Texas, 9-4.
• If these season series results remain, the tiebreaker would be determined by each club’s combined record against the other two teams. As of now, Seattle is 9-7 (.563), Houston is 11-12 (.478) and Texas is 9-10 (.474 win percentage).
• If a Wild Card spot also factors into a potential three-way tie, Houston would receive that position because of its head-to-head record vs. Texas.

All of these components could change by the day. The Mariners have the toughest path to the division crown, facing the Rangers seven times and Astros three times. Aside from its sets with Seattle, Texas also has a series at Anaheim; Houston hosts Kansas City this weekend and finishes the year at Arizona after visiting the Mariners.

Each of these teams has tumbled in September, so let’s start there. What’s behind that?

Brian McTaggart, Astros reporter: The Astros’ starting pitching, which was their strength last year, has cratered in the second half. Sure, Justin Verlander and Framber Valdez are still a formidable 1-2 combo at the top of the rotation, but it’s been hit or miss -- mostly miss -- after that. Rookies Hunter Brown and J.P. France haven’t been as effective in the second half, and Cristian Javier’s regression has been baffling, though he struck out 11 batters in five innings Wednesday. Plus, the Astros have been mediocre at home (39-39) since mid-August, which is unusual for a team that has typically enjoyed a decisive home-field advantage.

Daniel Kramer, Mariners reporter: A large part of it has been a far tougher schedule. In August, when they set a franchise record with 21 wins, the Mariners played only six of 27 games against teams above .500, whereas their September slate featured 20 of 29 games against winning teams. In this stretch, their offense has taken a significant dip, with a .623 OPS and a 28.5% strikeout rate with runners in scoring position. They’ve turned things around this week in Oakland, but the caveat there is the competition. A regression in run production has also coincided with some uncharacteristic hiccups from a pitching staff that has been among MLB’s best, as Seattle’s arms carry a 4.11 ERA and have surrendered 27 homers this month. The pitching was much better in Oakland, but again, it’s Oakland.

Kennedi Landry, Rangers reporter: It’s easy to look at the bullpen as the reason for Texas’ recent struggles, but the bullpen has been shaky all season. The real issue is health. The Rangers sent six players to the All-Star Game, but since the break, five of those players have spent time on the injured list: Corey Seager, Adolis García, Josh Jung, Jonah Heim and Nathan Eovaldi. Monday’s series opener against the Red Sox marked the first time since July 21 all five Rangers All-Star position players -- plus Eovaldi on the mound -- were in the same lineup. Injuries happen to every team, obviously, but Texas hasn’t fielded its best lineup in almost two months, and it’s shown in its record and offensive production. Sure, the record would be better without a plethora of blown saves in late August and early September, but it's hard not to imagine where this team would be if those games weren’t even close to begin with had the offense been healthy.

Do their issues seem fixable?

McTaggart: Javier had his best outing in months on Wednesday, which is a pretty big development if he can somehow build on that. A rotation of Verlander, Valdez and an effective Javier would set them up nicely in the postseason, but they’ll need France and/or Brown to pitch better as well. Will that happen? Only time will tell. Last year, the Astros had so much quality starting pitching depth that they put Luis Garcia and José Urquidy in the bullpen in the postseason. It’s all hands on deck this year.

Kramer: “It’s in there,” manager Scott Servais said after the Mariners were swept by the Dodgers last weekend, when asked if an offensive turnaround was possible. With Julio Rodríguez playing like an MVP in the second half, anything seems possible when their best player is clicking. The more concerning issue would be their pitching, largely because it’s carried the club all year. Logan Gilbert and George Kirby have shown some rare vulnerability, which has brought their workload situations more to the forefront to pair with rookies Bryan Woo and Bryce Miller, who’ve been outstanding but are being monitored closely. Beyond workhorse Luis Castillo, it’s a lot of innings for a lot of young arms. And including Castillo, all five starters have reached or will reach career highs in innings by season’s end at this rate.

Landry: Well, they’re healthy now. Jung and García injected life back into the lineup against the Red Sox, as the Rangers outscored them, 23-14, across the three-game set. Seager has hit his first slump of the season, but throughout the lineup, Texas looks like an offense that can compete with the AL’s best.

“It’s always good to get your guys back,” Rangers manager Bruce Bochy said after Tuesday’s win over the Red Sox. “We're getting down to the end here, so the timing is good that we are getting them healthy. I don't know what's going to happen, but at least you want your guys out there. And that's what we have right now. That’s a good thing.”

What’s the leading reason why the team you cover can win the division?

McTaggart: The schedule. With the Rangers and Mariners playing each other seven times in the final 10 games, the Astros can gain a game on somebody each night if they take care of business. Houston has three home games remaining against lowly Kansas City, but that’s the same Royals team that took two of three from them a week ago in K.C. Still, that’s a series Houston should win. The final six games are on the road, where the Astros have played very well this year; they’re 46-29 away from home.

Kramer: The schedule, which could also serve as the inverse to this question (more below). In one vein, the Mariners are in an enviable spot of controlling their own destiny by being able to do direct damage to the teams they’re racing against. They match up much better against Texas than the last time the two played, in Arlington in early June, when the Mariners were swept in three games due in large part to a resurgent offense. And they’ve throttled Houston all season -- but the question is if they can continue to do so at a time of year when the Astros thrive.

Landry: It almost feels silly for all three answers to be the schedule, but the Rangers control their own destiny just as much as the Mariners do. Texas has a 5-1 edge in the season series entering the weekend. Between the two series against Seattle, the Rangers will face an Angels team without Shohei Ohtani and Mike Trout. The path to the postseason is there for the taking.

And what’s the leading reason preventing your team from winning the division?

McTaggart: It’s all going to come down to starting pitching. The Astros’ offense, now that it’s healthy, is good enough to score with anyone. The bullpen isn’t quite as airtight as it was last year, but they have enough weapons and enough playoff experience to finish off games. So, back to the starters -- Verlander, Valdez, Javier, Brown and France. The onus will be on the starters to pitch effectively and deep into games to take the pressure off the offense and the bullpen.

Kramer: Also the schedule, which reaches its most daunting stretch yet. Essentially, their playoffs begin a week and a half early. Given Toronto’s resurgence on its way to the second AL Wild Card spot, there’s a good chance one of these AL West teams gets left out, and a tough week and a half could certainly sink Seattle toward what would be a highly disappointing idle October.

Landry: Remember that shaky bullpen? If anything stops the Rangers from getting into the postseason, it’ll be that. Even as every starting pitcher not named Jordan Montgomery has taken a step back this month, Texas is right in most of these games. Most of the club’s losses over the past month and a half have had a common denominator: late-inning bullpen collapses. Since Aug. 13 -- the beginning of the skid -- Texas is 3-for-16 in save opportunities. Since Aug. 1, the bullpen has a 5.26 ERA from the seventh to ninth innings.

Why is your team built for the postseason, should it advance?

McTaggart: Despite their struggles and vulnerabilities, the Astros are probably the last team anybody in the AL wants to face in October considering their recent postseason pedigree -- two World Series titles since 2017, four AL pennants (‘17, ‘19, ‘21-22) and six consecutive trips to the AL Championship Series. Alex Bregman has played in 92 postseason games, Jose Altuve 86, Martín Maldonado 54, Kyle Tucker 51 and Yordan Alvarez 47. Jeremy Peña was the World Series MVP last year. No moment will be too big for the Astros, but they’ll have to get their pitching turned around. They rolled through the playoffs last year, going 11-2, behind a dominant pitching staff.

Kramer: Their pitching is built for October, especially shorter series -- though that obviously will hinge on Kirby and Gilbert looking more like themselves from earlier this year. Castillo showed last fall that he’s as wired for the postseason as any MLB pitcher. Kirby also relishes the grander stage (he has a 2.36 ERA this year against above-.500 teams and a 5.07 clip against losing clubs). And before Sunday, Gilbert had been among the AL’s most consistent starters. (Seattle had been 10-3 behind him since July.) And their bullpen has enough different looks and power arms that make it, when it’s not gassed, one of the league’s deepest. The relievers will probably receive an extra injection via Woo and Miller, too. The Mariners deliberately built their roster this way for this time of year.

Landry: There’s a lot to like about the Rangers, from the high-powered offense featuring 2020 World Series MVP Corey Seager, to a strong and steady Jordan Montgomery atop a rotation that has lost Jacob deGrom and Max Scherzer. But the biggest thing that makes this Texas club ready for the postseason lies at the top. Bochy was a three-time World Series-winning manager with the Giants in 2010, ‘12 and ‘14 and added another appearance with the Padres in 1998. The pressure of a pennant race and the competition that comes with it is part of what drew Bochy out of retirement. He’s no doubt been a huge part of the Rangers’ success this season. He’s ready to bring that into October.