Kansas City Royals vs Seattle Mariners Prediction – 6/30/2025

The Seattle Mariners will host the Kansas City Royals on June 30, 2025, in what is the first game of a series between these two squads. Currently, the Mariners hold a record of 43-40, placing them in a competitive position in the American League, while the Royals are struggling at 39-45. A noteworthy aspect of this matchup is the Mariners' solid ranking in the Power Rankings, where they boast the 7th best bullpen in MLB, a stark contrast to the Royals' 14th place.

In their last outing, the Mariners' George Kirby will be looking to bounce back despite a less-than-ideal 1-4 record this season, accompanied by an ERA of 5.40. However, projections suggest he has been somewhat unlucky and is expected to perform better, projecting to pitch 6.3 innings while allowing only 2.3 earned runs. Kirby's low walk rate could be advantageous against the Royals, who have been the least patient offense in the league.

Conversely, Kansas City's Michael Wacha, with a respectable ERA of 3.33, is projected to pitch 5.6 innings but could face challenges against the Mariners' potent lineup, ranked 10th overall in MLB offense. The Mariners have excelled in power, ranking 7th in home runs, which could exploit Wacha's tendency to give up hits, as he projects to allow 5.0 hits and 1.5 walks today.

With a game total set at a low 7.5 runs, the Mariners are favored with a moneyline of -160, hinting at their potential to secure a win against a Royals team that has struggled to find offensive rhythm, ranking 26th overall in MLB. As both teams seek to establish momentum, the Mariners may have the upper hand with their strong bullpen and dynamic offense.

Quick Takes Kansas City Royals:

Michael Wacha's change-up usage has decreased by 6.3% from last year to this one (32.3% to 26%) .

• Because change-ups are one of the most effective pitches to use, a pitcher who alters his pitch mix to use them less often may see less success as a result, particularly if he uses his fastball more instead.

Extreme groundball batters like Salvador Perez generally hit better against extreme flyball pitchers like George Kirby.

• This mostly has to do with the way the hitter's swing plane interacts with the pitch trajectory, and it can create boosted performance across all categories and hidden value few are considering.

Salvador Perez pulls many of his flyballs (37.1% — 95th percentile) and has the good fortune of hitting them towards MLB's 8th-shallowest LF fences in today's matchup.

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

Quick Takes Seattle Mariners:

Out of all SPs, George Kirby's fastball velocity of 95.5 mph grades out in the 88th percentile this year.

• Velocity is a key component to fastball success in generating strikeouts and preventing runs.

Luke Raley is penciled in 6th on the lineup card in today's game, which would be a downgrade from his 71% rate of hitting in the top-half of the lineup this year.

• The lower in the order a player bats, the fewer plate appearances he will get and the fewer opportunities he will get to hit the Over for every market. A player who hits lower in the order than he normally does may provide extra value opportunity since the market may be based on him hitting higher.

Cal Raleigh, the Mariners's expected catcher in today's game, projects as an elite pitch framer according to the leading projection system (THE BAT).

• Pitch framing is a catcher's ability to make a ball look like a strike to the umpire, "stealing" strikes for his pitcher. This leads to more positive outcomes (like strikeouts) and fewer negative ones (like walks or earned runs).

Game Trends

• The Seattle Mariners have hit the Game Total Over in 19 of their last 30 games at home (+8.30 Units / 26% ROI)
• The Kansas City Royals have hit the Team Total Under in 53 of their last 75 games (+29.95 Units / 34% ROI)
• Jac Caglianone has hit the Hits Runs and RBIs Under in 16 of his last 20 games (+10.70 Units / 40% ROI)

Kansas City Royals vs Seattle Mariners Prediction

Predicted Final Score: Kansas City Royals 3.61, Seattle Mariners 4.02

• Date: June 30, 2025
• Venue: T-Mobile Park
• Starting Pitchers:
  • Michael Wacha - Royals
  • George Kirby - Mariners

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