The 2026 division previews continue with the AL West. To help with evaluations, a crude runs created per game is calculated from Musings Marcel projections for both batters and pitchers. I then average these for the core of the team. The nine position players, the five starting pitchers, and the closer. I weight the pitchers as 90% starters, 10% closer. The selection of players comes from the FanGraphs Roster Resource.

The bottom line is a Core Winning Percentage based on the RC/G of the core batters and core pitchers using the Pythagorean method. You can see the spreadsheet with the data here.

Note that the core winning percentage (CWP) is going to be high, often the core is going to be over .500. We are basically looking at the best players on the team. Don’t take that as a prediction of team winning percentage, take it as a way to compare teams in a division.

Seattle Mariners

• Position Player RC/G Average: 5.23
• Pitcher RC/G Average: 3.92
• Core Winning Percentage: .640

Seattle returns as the favorite in the AL West, and the numbers bear that out. The Mariners project to the best pitching staff in the division by a comfortable margin, and a balanced offense with no obvious soft spots gives them the depth to grind through a long season. Their .640 core winning percentage is the highest in the division and one of the higher marks in the American League.

The reason is the rotation. George Kirby (3.97 RC/G), Bryan Woo (3.13), Logan Gilbert (3.50), and Luis Castillo (4.41) give the Mariners four starters who all project as above-average or better. Woo in particular is an outstanding projection — 3.13 RC/G puts him among the best starters in the American League. Emerson Hancock (5.11) is the one soft spot in the rotation, and even he is offset by how good the top four are. Add Munoz closing at 2.97 and this is the best pitching staff in the division by a significant margin.

The offense is solid rather than spectacular. Cal Raleigh (6.06 RC/G at catcher) is one of the better hitting catchers in baseball, and Julio Rodriguez (5.74 in center) gives Seattle a homegrown star still ascending at seasonal age 25. Josh Naylor (5.75 at first) is a consistent run producer. The up-the-middle average of 5.19 leads the division, meaning the Mariners are strong precisely where teams are hardest to upgrade. The lineup lacks a superstar on the level of Judge or Witt, but there are no soft spots either.

Brendan Donovan (5.58 at third) is an underrated piece of this roster, projecting as one of the better third basemen in the AL West. Randy Arozarena (5.17 in left) and Luke Raley (4.99 in right) round out a deep, if unspectacular, outfield.

Seattle looks like the team to beat in the AL West for the second straight season.

Pinto writes: It’s prime time for Rodriguez, and I very much hope to see him take his offense to the next level as he enters what should be the best years of his career. Maybe a seven or eight WAR season?

Texas Rangers

• Position Player RC/G Average: 5.21
• Pitcher RC/G Average: 4.20
• Core Winning Percentage: .606

Corey Seager at 6.97 RC/G is the offensive centerpiece of a Rangers lineup that is more balanced than it might appear at first glance. Wyatt Langford (5.60 in left), Brandon Nimmo (5.24 in right), and Evan Carter (5.30 in center) give Texas a strong outfield. Joc Pederson (5.11 at DH) is a useful run producer. The up-the-middle average of 5.38 is the best in the division, anchored by Seager at shortstop.

The rotation has a genuine ace in Jacob deGrom at 3.59 RC/G. DeGrom’s history of injury means every projection for him comes with an asterisk — the Marcels can project his performance when healthy, but not how often he will take the ball. If he pitches 170 innings, the Rangers rotation looks formidable. Jack Leiter (4.47) and Nathan Eovaldi (3.67) give Texas two more above-average arms. MacKenzie Gore (4.94) and Jacob Latz (4.36) fill out the back of the rotation adequately. Robert Garcia (4.19) is a serviceable closer.

The Rangers project tightly behind Seattle, and the gap between them is narrower than it might look. If deGrom stays healthy, Texas has the pitching to challenge the Mariners all summer. That is a big if, but it has been a big if every season deGrom has been healthy, and he has occasionally delivered on it in spectacular fashion.

Pinto writes: I wonder how much being around deGrom and Eovaldi will help Gore. His FIPs were much better than his ERAs over the last two seasons, so maybe a better defense, combined with advice from two great veterans might help Gore go to the next level.

Oakland Athletics

• Position Player RC/G Average: 5.50
• Pitcher RC/G Average: 4.64
• Core Winning Percentage: .584

The Athletics project to the best offensive core in the division at 5.50 RC/G, which may surprise those who have not been paying attention to what Oakland has been building. Nick Kurtz at first base is the centerpiece. He projects to 8.35 RC/G — an extraordinary number that reflects nearly 500 plate appearances in 2025 that were outstanding enough to produce this heavily regressed figure. The real Kurtz may be even better. He gives the Athletics the kind of young star around which franchises are built.

Brent Rooker (6.17 at DH) and Jacob Wilson (5.91 at shortstop) are legitimate offensive contributors. Shea Langeliers (5.09 at catcher) is a useful bat behind the plate. Tyler Soderstrom (5.59) in left field adds another powerful projection to a lineup full of them. The concern is that several of these players are projecting at levels they have not yet fully demonstrated over full seasons, and the Marcels are working with limited data on more than one of them.

The pitching, however, is the reason the Athletics do not challenge for the division title. Luis Severino (5.09 RC/G) and Jack Kochanowicz (5.90 at the back of the rotation) are significant liabilities. Jeffrey Springs (4.57) and Aaron Civale (4.78) are mid-rotation quality at best. Hogan Harris closing at 4.88 is the weakest closer projection in the division. No matter how well the offense performs, it is difficult to win consistently when the pitching gives back runs at this rate.

The Athletics are a fascinating team — potentially one of the best offenses in the AL, but held back by pitching that projects to struggle. A playoff run feels unlikely unless the rotation dramatically outperforms.

Pinto writes: I very much look forward to Chen Zhong-Ao Zhuang joining the Athletics rotation. I hope he has broad shoulders.

Houston Astros

• Position Player RC/G Average: 5.30
• Pitcher RC/G Average: 4.62
• Core Winning Percentage: .568

Yordan Alvarez at 7.58 RC/G remains one of the most feared hitters in baseball, and he anchors an Astros lineup that still has Jose Altuve (5.60 at second base) and Issac Paredes (5.93 at third) as productive contributors. The offense projects to a solid 5.30 RC/G average, enough to keep Houston competitive on most nights.

The rotation, however, is a concern. Lance McCullers Jr. projects to 6.17 RC/G, a number that reflects both his injury history and how far he has fallen from his peak. Having McCullers in the rotation as a fifth starter is manageable; having him projected as one of the worse arms on the staff is a sign of how thin the Houston pitching depth has become. Cristian Javier (4.82) and Hunter Brown (3.87) are the most reliable arms. Tatsuya Imai (4.50) is an interesting addition. Bryan Abreu (3.48) is a solid closer.

The Astros’ up-the-middle average of 5.01 is adequate, with Altuve at second and Carlos Correa (5.10) at shortstop providing the veteran core the organization has leaned on for years. This still looks like a .500-plus team that will compete for a wild card, but the days of the Astros being a dominant force in the AL West appear to be behind them for now.

Pinto writes: Looks like Houston is setting up to take one more shot at the playoffs before going into rebuild mode. I suspect they may want to see the shape of the new CBA before they decide how build a new winner.

Los Angeles Angels

• Position Player RC/G Average: 4.94
• Pitcher RC/G Average: 4.92
• Core Winning Percentage: .501

Mike Trout projects to 5.77 RC/G in center field. That is actually a subdued number by Trout’s historical standards, reflecting both the Marcels building in age-related decline at seasonal age 35 and the accumulated weight of his injury history in recent years. He is still the best player on this team, and on the days he takes the field, the Angels are a more interesting offensive club.

The problem is that a .501 core winning percentage means even with Trout healthy, the Angels’ best players barely project to break even. Zach Neto (5.46 at shortstop) and Nolan Schanuel (5.41 at first) are the two brightest offensive spots outside of Trout. Yoan Moncada (5.12 at third) adds some punch. But Adam Frazier at second base (3.97) and Jo Adell in right (4.67) are below-average contributors at their positions, and the pitching staff is one of the weakest in the division.

Jack Kochanowicz (5.90 RC/G) and Reid Detmers (5.08) are the rotation’s two biggest liabilities. Jose Soriano (4.13) projects as the most effective starter on the staff, which is a modest ceiling for an ace. Kirby Yates (4.10) is the one reliable piece in the bullpen as the closer. The Angels lead the division in up-the-middle average at 4.87, but that is a function of Trout and Neto rather than genuine organizational depth.

The Angels have now missed the playoffs for eleven consecutive seasons. The core winning percentage of .501 suggests that streak is not about to end in 2026. Until the front office finds a way to build a rotation worthy of Trout’s remaining seasons, Anaheim will continue to watch October from home.

Predictions

Here is how I see the probabilities of the teams winning the division.

• Seattle Mariners 42%
• Texas Rangers 28%
• Oakland Athletics 15%
• Houston Astros 12%
• Los Angeles Angels 3%

The AL West looks like a two-team race between Seattle and Texas, with the Mariners holding a meaningful edge in pitching depth. The Athletics are the wild card in this division — if the offense performs to its projection and the rotation finds more consistency than expected, Oakland could surprise. The Astros remain competitive but are no longer the dominant force they were. The Angels need a rotation overhaul before they can seriously contend, and with Trout’s window narrowing, time is not on their side.

Pinto writes: I might go 40-30 on the Mariners and Rangers as the top pair. I’m also waiting to see what the Athletics have up their pitching sleeve.