After a brutal August gauntlet against playoff contenders and heavy travel, the Seattle Mariners returned home expecting a comfortable series against the Oakland Athletics. Instead, the 2026 Mariners’ confounding nature persisted, dropping the series to a depleted A’s roster. Only Bryan Woo’s heroics prevented a sweep. Seattle salvaged a series win over Texas previously, but a sweep was necessary to revive flickering playoff odds, which sit at 6.2% as of Thursday night. The Mariners now arrive in Sacramento essentially needing perfection.
Series Schedule and Win Probabilities
| Game | Time (PT) | Mariners Starter | Athletics Starter | Mariners Win% | Athletics Win% |
|---|---|---|---|---|---|
| Game 1 | Friday, September 11 | 6:40 pm | RHP George Kirby | LHP Jeffrey Springs | 64.1% | 35.9% |
| Game 2 | Saturday, September 12 | 6:40 pm | RHP Bryan Woo | LHP Gage Jump | 60.8% | 39.2% |
| Game 3 | Sunday, September 13 | 1:05 pm | RHP Bryce Miller | RHP Jacob Lopez | 58.1% | 41.9% |
Team Overview: Two Struggling Clubs
| Category | Mariners | Athletics | Edge |
|---|---|---|---|
| Batting (wRC+) | 100 (9th in AL) | 95 (12th in AL) | Mariners |
| Fielding (FRV) | -42 (15th) | -38 (14th) | Athletics |
| Starting Pitching (FIP-) | 99 (8th) | 119 (15th) | Mariners |
| Bullpen (FIP-) | 103 (11th) | 102 (8th) | Athletics |
Neither team ranks above average in most categories. The Mariners hold a slight edge in starting pitching and offense, while Oakland’s bullpen and defense grade out marginally better. Both lineups and defenses are below average, making starting pitching the critical differentiator.
Athletics Lineup: A Roster Gutted by Injury
From last week’s series preview: The biggest reason why the Athletics have struggled so much since June is because their lineup has been absolutely gutted by injuries; Brent Rooker (knee), Shea Langeliers (knee), Nick Kurtz (thumb), Tyler Soderstrom (hip), and Jacob Wilson (shoulder) have all succumbed to season-ending injuries. Those five are the core the team was building around so to have all of them sidelined at once has been a huge blow. There have been some positives despite all the struggles. Zack Gelof has been the team’s best hitter when he’s been on the field — he’s missed a bunch of time with a handful of minor scrapes and bruises. The demise of Lawrence Butler has been greatly exaggerated as well; since June 10, he’s put up a 131 wRC+ with nine home runs.
| Player | Pos | Bats | PA | K% | BB% | ISO | wRC+ |
|---|---|---|---|---|---|---|---|
| Henry Bolte | CF | R | 407 | 27.8% | 8.1% | 0.126 | 111 |
| Jeff McNeil | 1B | L | 464 | 11.2% | 5.8% | 0.103 | 85 |
| Zack Gelof | 3B | R | 373 | 25.5% | 7.2% | 0.207 | 109 |
| Lawrence Butler | RF | L | 473 | 26.4% | 11.6% | 0.138 | 85 |
| Carlos Cortes | LF | L | 344 | 16.3% | 8.1% | 0.142 | 97 |
| Max Muncy | DH | R | 273 | 31.9% | 7.7% | 0.163 | 87 |
| Donovan Walton | 2B | L | 124 | 16.9% | 13.7% | 0.168 | 126 |
| Alika Williams | SS | R | 200 | 22.5% | 4.0% | 0.156 | 88 |
| Jonah Heim | C | S | 307 | 19.5% | 6.5% | 0.173 | 69 |
Game 1: George Kirby vs. Jeffrey Springs
Pitching Matchup
| Pitcher | IP | K% | BB% | HR/FB% | GB% | ERA | FIP |
|---|---|---|---|---|---|---|---|
| Jeffrey Springs | 130 | 18.2% | 9.1% | 17.9% | 34.4% | 6.02 | 6.07 |
| George Kirby | 159.1 | 19.3% | 5.5% | 11.0% | 43.7% | 4.18 | 3.81 |
Jeffrey Springs Pitch Arsenal
| Pitch | Usage vs RHB | Usage vs LHB | Velocity | Stuff+ | Whiff+ | BIP+ | xwOBA |
|---|---|---|---|---|---|---|---|
| Four-seam | 43.1% | 45.2% | 91.4 | 89 | 73 | 93 | .357 |
| Cutter | 3.5% | 0.8% | 87.8 | 91 | |||
| Changeup | 32.0% | 4.9% | 79.5 | 111 | 115 | 83 | .267 |
| Slider | 16.3% | 41.6% | 84.1 | 97 | 69 | 67 | .383 |
| Sweeper | 5.0% | 7.4% | 77.4 | 97 | 27 | 116 | .409 |
From a previous series preview: Jeffrey Springs has managed to survive pitching in Sutter Health Park by generating a ton of weak contact. His .255 BABIP was the ninth lowest among qualified pitchers last year and it’s even lower this season. He allows a ton of contact in the air and all that elevated contact hasn’t turned into damage like you might expect. It’s mostly just weak fly balls that are easily caught. He’s also throwing a little harder this season, though his strikeout-to-walk ratio is almost an exact mirror of what he posted last year. His best pitch is still his changeup and that’s what allows him to run a slightly reverse platoon split. After a decent start to the season, Springs has been absolutely terrible over the last three months; since the beginning of June, his ERA is over eight! The last time he faced the Mariners, though, he went seven scoreless.
Kirby holds a clear advantage in command and FIP, but Springs’ unique ability to suppress hard contact at Sutter Health Park makes him dangerous despite poor surface numbers. The changeup remains his weapon against right-handed hitters.
Game 2: Bryan Woo vs. Gage Jump
Pitching Matchup
| Pitcher | IP | K% | BB% | HR/FB% | GB% | ERA | FIP |
|---|---|---|---|---|---|---|---|
| Gage Jump | 96.2 | 24.9% | 10.6% | 9.6% | 38.4% | 5.12 | 3.74 |
| Bryan Woo | 156.1 | 25.0% | 5.2% | 9.8% | 37.6% | 4.03 | 3.34 |
Gage Jump Pitch Arsenal
| Pitch | Usage vs RHB | Usage vs LHB | Velocity | Stuff+ | Whiff+ | BIP+ | xwOBA |
|---|---|---|---|---|---|---|---|
| Four-seam | 48.1% | 42.0% | 96.3 | 101 | 106 | 100 | .348 |
| Sinker | 3.4% | 10.9% | 95.1 | 88 | |||
| Changeup | 12.4% | 0.2% | 87.6 | 94 | 90 | 129 | .298 |
| Curveball | 12.7% | 4.2% | 82.3 | 126 | 83 | 89 | .260 |
| Slider | 22.8% | 21.7% | 87.2 | 116 | 86 | 86 | .310 |
| Sweeper | 0.7% | 21.0% | 83.8 | 116 | 110 | 77 | .194 |
From a previous series preview: The Athletics top pitching prospect entering the season, Gage Jump made his major league debut at the end of May — against the Mariners no less — and has pitched through an up-and-down rookie campaign. He’s shown flashes of brilliance at times, but he’s also been prone to big blowups that spiral out of control. He’s got three different breaking balls that make up the bulk of his pitch mix with a four-seamer as the foundation and a sinker and changeup to round out the repertoire. His low arm angle helps his fastball play up from an already impressive 96 mph from the left side, giving the pitch excellent movement across both planes. Right now, he’s much more of a thrower than a pitcher, filling the middle of the zone with his hard stuff and spraying his secondaries around the edges of the zone. That lack of command is the one thing holding him back from truly bringing the entire package together. Jump has a bright future ahead of him. However, he’s been getting hit hard, much of it on the fastball, a pitch that should by the metrics be a killer. He should be fun to watch.
Woo’s elite command (5.2% walk rate) contrasts sharply with Jump’s 10.6% walk rate. Jump’s three breaking balls and high-velocity four-seamer offer high upside, but inconsistent command leads to volatile outings. Seattle’s patience at the plate could force Jump into high-leverage mistakes.
Game 3: Bryce Miller vs. Jacob Lopez
Pitching Matchup
| Pitcher | IP | K% | BB% | HR/FB% | GB% | ERA | FIP |
|---|---|---|---|---|---|---|---|
| Jacob Lopez | 111 | 21.1% | 10.8% | 11.0% | 31.6% | 4.78 | 4.99 |
| Bryce Miller | 102.1 | 24.3% | 7.0% | 14.2% | 37.2% | 4.22 | 4.29 |
Jacob Lopez Pitch Arsenal
| Pitch | Usage vs RHB | Usage vs LHB | Velocity | Stuff+ | Whiff+ | BIP+ | xwOBA |
|---|---|---|---|---|---|---|---|
| Four-seam | 30.8% | 43.2% | 90.4 | 92 | 95 | 120 | .275 |
| Sinker | 2.2% | 5.9% | 89.7 | 81 | |||
| Cutter | 24.7% | 8.0% | 86.2 | 87 | 106 | 105 | .343 |
| Changeup | 11.3% | 0.0% | 82.6 | 82 | 70 | 72 | .406 |
| Slider | 31.0% | 43.0% | 76.2 | 116 | 89 | 115 | .237 |
From a previous series preview: Jacob Lopez was a surprise last year. Never regarded as a top prospect, and a throw-in in the Jeffrey Springs trade a few years ago, he had a stretch of 13 starts last summer where he ran a 2.64 ERA and a 3.08 FIP. He ran into the Mariners on August 24, allowed nine runs, and was placed on the IL with an elbow strain the next day. His raw stuff just isn’t that impressive; his fastball barely averages 90 mph and a slow looping slider is hardly optimized for whiffs. Still, some deception in his throwing motion allows his stuff to play up a bit. After a rough start to the year, Lopez has been a much more solid starter in the second half: ERA (first half | second half): 6.83 | 2.75 Opponents’ Slash Line: .293/.381/.495 | .209/.288/.350 Hopefully Lopez can find one last first-half outing in him.
Miller carries a higher strikeout rate but surrenders more home runs (14.2% HR/FB). Lopez’s second-half transformation (2.75 ERA, .209/.288/.350 opponent slash) makes him a tougher out than full-season numbers suggest. His slider (116 Stuff+) and deceptive delivery neutralize right-handed bats. The Mariners saw Lopez at his worst on August 24; the version they face Sunday resembles the effective second-half starter.
AL West and Wild Card Standings Context
AL West
| Team | W-L | W% | GB | Run Diff | Recent Form |
|---|---|---|---|---|---|
| Astros | 75-72 | .510 | — | -40 | L-L-W-L-W |
| Rangers | 72-75 | .490 | 3.0 | -41 | L-W-W-L-L |
| Mariners | 69-78 | .469 | 6.0 | -74 | L-W-L-W-W |
| Athletics | 59-88 | .401 | 16.0 | -187 | W-L-W-L-W |
| Angels | 56-90 | .384 | 18.5 | -73 | W-L-L-W-W |
AL Wild Card Race
| Team | W-L | W% | WC GB | Run Diff | Recent Form |
|---|---|---|---|---|---|
| Yankees | 84-62 | .575 | +10.5 | +131 | W-L-W-W-W |
| Red Sox | 80-67 | .544 | +6.0 | +82 | W-W-W-L-L |
| Guardians | 74-73 | .503 | — | -16 | L-W-L-W-L |
| Blue Jays | 73-74 | .497 | 1.0 | -39 | W-L-L-W-L |
| Rangers | 72-75 | .490 | 2.0 | -41 | L-W-W-L-L |
| Orioles | 71-76 | .483 | 3.0 | -27 | L-L-W-L-W |
The Mariners gained a game in the Wild Card standings this week and are now closer to the final Wild Card spot than the AL West lead. Houston plays Tampa Bay and Texas faces Arizona this weekend. Minnesota and Cleveland meet head-to-head — a Twins series win would help Seattle by keeping the third Wild Card threshold below .500. Baltimore and Toronto also square off; chaos benefits the Mariners, though an Orioles series win is the preferred outcome.
Bottom Line
Seattle’s path requires a sweep against a bad but feisty Oakland team playing its final home series at Sutter Health Park. The pitching matchups favor the Mariners on paper, but Springs’ home-ballpark mastery, Jump’s electric stuff, and Lopez’s second-half revival present genuine upset risk. The offense must capitalize against a vulnerable Athletics bullpen and defense. With playoff odds hovering near 6%, every game carries elimination-level stakes.
