Will Seattle’s Pitching Outlast the Mets’ Bullpen Game? Expert Breakdown

The Seattle Mariners and New York Mets are locked in a tight battle for postseason positioning as they meet in the rubber match of their three-game series on August 17, 2025. With both teams sitting in second place in their respective divisions, every win carries heightened importance as the playoff race heats up.

Seattle, coming off an 11-9 offensive explosion on August 15 but stifled in a 3-1 loss the following night, will look to regain momentum behind right-hander George Kirby. Meanwhile, the Mets, relying on a bullpen game with Clay Holmes opening, must overcome significant pitching injuries to secure a series victory at Citi Field.

This matchup presents an intriguing contrast in styles—the Mariners’ balanced attack against a Mets team that has outperformed expectations despite a depleted roster. Key factors such as starting pitching stability, bullpen depth, and recent offensive trends will play a crucial role in determining the outcome.

Adding another layer of intrigue is the strength of schedule each team has faced in recent weeks, along with injuries impacting both sides. The Mariners are missing key contributors like Bryce Miller and Victor Robles, while the Mets are without Jesse Winker, Jose Siri, and multiple relievers, including Adbert Alzolay and A.J. Minter.

As these two wild card contenders collide, the question becomes: Which team has the edge in this pivotal late-season showdown? Will Seattle’s steady rotation and disciplined lineup prevail, or can New York’s patchwork pitching staff tilt the scales in their favor?

In this breakdown, we’ll dive deep into:

• Starting pitching matchups and bullpen concerns

• Offensive trends and key player absences

• Advanced metrics, including Pythagorean win expectations and strength of schedule

• Weather and ballpark factors that could influence scoring

• How betting markets are reacting to this evenly matched contest

AI Betting Models for Predictions

• BetQL: Mets +0.5 (Projected Score: SEA 3.8 – NYM 4.2)

• ESPN Matchup Predictor: 55% Mets (Projected Score: SEA 4.1 – NYM 4.5)

• SportsLine (Projection Model): Mets ML (+108) (Projected Score: SEA 3.9 – NYM 4.3)

• PECOTA: SEA 4.0 – NYM 4.1

• FanGraphs (ZiPS): SEA 3.7 – NYM 4.4

Average AI Prediction:

• Seattle Mariners: ~3.9 runs

• New York Mets: ~4.3 runs

Our Enhanced Prediction (Pythagorean Theorem + Strength of Schedule + Injuries + Trends)

A. Pythagorean Win Expectation

• Mariners:

  • Runs Scored (RS): 4.3 per game

  • Runs Allowed (RA): 3.9 per game

  • Pythagorean Win% = (RS² / (RS² + RA²)) = ~55%

• Mets:

  • RS: 4.4 per game

  • RA: 4.2 per game

  • Pythagorean Win% = ~52%

Slight edge to Mariners (but close).

B. Strength of Schedule (Last 30 Days)

• Mariners: Faced #8 toughest schedule (opponents avg. .520 win%)

• Mets: Faced #14 toughest schedule (opponents avg. .505 win%)
  Mariners have faced slightly tougher competition.

C. Starting Pitcher Analysis

• George Kirby (SEA):

  • 3.45 ERA, 1.10 WHIP, 8.2 K/9

  • Last 3 starts: 2.89 ERA

  • Strong control pitcher, but Mets hit RHP well (.745 OPS last 30 days).

• Clay Holmes (NYM – Opener, Bullpen Game?)

  • 3.80 ERA, 1.25 WHIP

  • Mets bullpen is depleted (multiple key injuries).

  • Likely a bullpen game, which hurts NYM’s chances.

D. Key Injuries & Trends

• Mariners Missing: Bryce Miller (SP), Victor Robles (OF) – hurts depth.

• Mets Missing: 6 relievers + key hitters (Winker, Siri) – bullpen is a major concern.

• Recent Form:

  • SEA: 2-3 last 5

  • NYM: 2-3 last 5

  • Trend: Mets have been slightly better, but bullpen issues loom.

E. Weather & Ballpark Factors

• Citi Field: Slight pitcher’s park (suppresses HRs).

• Weather: Clear, light wind (~5 mph) – neutral conditions.

3. Final Prediction

• Our Projected Score: SEA 4.2 – NYM 3.9 (Mariners slight edge due to Mets’ bullpen issues).

• Combined with AI Models:

  • AVG Projection: SEA 4.0 – NYM 4.1 (Mets +0.1 runs).

4. Recommended Bet

• Lean: Seattle Mariners ML (-115 or better)

  • Kirby is more reliable than a Mets bullpen game.

  • Mets’ injuries to relievers could be decisive late.

• Alternative: Under 8.5 (-110)

  • Both teams have decent pitching, and the total seems slightly high.

Pick

• Take the Seattle Mariners -108 Moneyline ***LOSE***

Reasoning: The Mets’ bullpen injuries and Kirby’s consistency give Seattle the edge in a close game. The AI models slightly favor the Mets, but our deeper analysis suggests Seattle is the better play.