Cleveland Guardians vs Seattle Mariners Prediction – 6/13/2025

As the Seattle Mariners prepare to host the Cleveland Guardians on June 13, 2025, both teams are looking to build momentum after contrasting performances in their last games. The Guardians come off a strong 11-2 victory over the Cincinnati Reds, while the Mariners suffered a disappointing 5-2 loss to the Arizona Diamondbacks. With the Mariners sitting at 33-34 and the Guardians at 35-32, this matchup holds significance as both teams aim to improve their standings in an increasingly competitive American League.

On the mound, the Mariners are projected to start Luis Castillo, who has had an average season with a 4-4 record and a solid 3.31 ERA. However, his 4.26 xFIP suggests he may have been a bit fortunate so far. Castillo's ability to strike out 5.3 batters per game is decent, but he also projects to allow a concerning 4.8 hits and 1.8 walks on average today. In contrast, Gavin Williams of the Guardians has a 5-3 record with a 3.86 ERA, and while he's also projected to allow 2.4 earned runs, his 4.40 xERA indicates he might be in a similar position as Castillo regarding luck.

Offensively, the Mariners rank 13th in the league, buoyed by a powerful lineup that has hit the 6th most home runs this season. The Guardians, however, struggle offensively, ranking 25th in the league, which could be a significant factor in this matchup.

With a Game Total set at a low 7.0 runs and the Mariners holding a moneyline of -130, betting markets suggest a close contest. Given the Mariners' offensive capabilities and Castillo's potential to outperform his projections, they may have the edge in this pivotal game.

Quick Takes Cleveland Guardians:

Compared to the average hurler, Gavin Williams has been granted a longer leash than the typical pitcher this year, tallying an additional 7.6 adjusted pitches each start.

• Pitchers with a longer leash are more likely to go deeper into games and record more outs.

Nolan Jones is apt to have the upper hand against every reliever for the game's entirety, since the bullpen of the Seattle Mariners has just 1 same-handed RP.

• Hitters perform worse against pitchers of the same handedness (i.e. righty-vs-righty), and being able to avoid those matchups against the bullpen boosts performance and creates hidden edge.

Cleveland Guardians bats as a group grade out 28th- in Major League Baseball for power this year when using their 6.9% Barrel%.

• Barrel% measures how often a player hits the ball at the optimal exit velocity and launch angle and is a terrific measure of underlying power.

Quick Takes Seattle Mariners:

The Cleveland Guardians have 7 hitters in the projected lineup that will have the handedness advantage against Luis Castillo in this matchup, which is especially precarious given his large platoon split.

• Right-handed pitchers perform worse against left-handed hitters (and visa-versa). If several hitters hold this advantage against the pitcher, it can have a huge impact on whether he will perform well or struggle on any given day.

Based on Statcast data, the leading projection system (THE BAT X)'s version of Expected HR per 600 plate appearances (38.4) may lead us to conclude that Cal Raleigh has experienced some positive variance this year with his 54.2 actual HR/600.

• xHR uses highly advanced Statcast data to measure a player's home run ability more accurately than actual home runs can.

Cal Raleigh pulls a lot of his flyballs (43.2% — 100th percentile) and will have a big advantage hitting them towards the league's 4th-shallowest RF fences today.

• This player's skill set matches up particularly well with the park he's in today, which may lead to better-than-usual performance.

Game Trends

• The Seattle Mariners have hit the Game Total Over in 34 of their last 60 games (+7.70 Units / 12% ROI)
• The Cleveland Guardians have hit the Game Total Under in 19 of their last 32 games (+5.75 Units / 16% ROI)
• Cal Raleigh has hit the Total Bases Over in 16 of his last 25 games at home (+7.85 Units / 26% ROI)

Cleveland Guardians vs Seattle Mariners Prediction

Predicted Final Score: Cleveland Guardians 4.02, Seattle Mariners 3.93

• Date: June 13, 2025
• Venue: T-Mobile Park
• Starting Pitchers:
  • Gavin Williams - Guardians
  • Luis Castillo - Mariners

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