The Mariners make the trip to Kansas City to face the Royals! These two teams have been two of the best teams in the AL and are in the playoff race in a loaded league. Seattle won the previous series this year 2-1 at home in early May. The Mariners are the hotter team, when compared to the Royals leading into this matchup. Our MLB odds series has our Mariners-Royals prediction, odds, and pick for Saturday.

Mariners-Royals Projected Starters 

Luis Castillo vs. Alec Marsh

Luis Castillo (5-6) with a 2.99 ERA and a 1.15 WHIP

Last Start: Pitched seven innings and gave up zero runs and two hits with three walks and six strikeouts in a Mariners win.

2024 Road Splits: (2-3) 3.03 ERA

Alec Marsh (4-3) with a 3.76 ERA and a 1.15 WHIP

Last Start: Pitched five innings and gave up five runs on seven hits with three walks and three strikeouts in a Royals loss.

2024 Home Splits: (2-1) 3.86 ERA

Here are the MLB Odds, courtesy of FanDuel. 

MLB Odds: Mariners-Royals Odds

Seattle Mariners: -1.5 (+122)

Moneyline: -136

Kansas City Royals: +1.5 (+116)

Moneyline: +114

Over: 8.5 (-122)

Under: 8.5 (+100)

How to Watch Mariners vs. Royals

Time: 4:10 pm ET

TV: ROOT Sports

Stream: fuboTV (Click for free trial)

Why The Mariners Will Cover The Spread/Win

The Mariners have been red-hot recently and have a 36-28 record. They have won four out of their last five games leading into this series. The Mariners have struggled behind the plate this season, but their pitching staff is a top-10 unit in the MLB. Julio Rodriguez, Cal Raleigh, Mitch Haniger, Jorge Polanco, Ty France, and Mitch Garver are standouts on offense despite their struggles. Luis Castillo, Logan Gilbert, and Bryce Miller have all been at varying levels of good to great for the Mariners pitching-wise and have carried the team when needed.

The Mariners are starting Luis Castillo at pitcher where he has a 5-6 record, a 2.99 ERA, and a 1.15 WHIP. Through 78.1 innings, he has allowed 28 runs on 68 hits with 22 walks and 81 strikeouts. In his 13 starts this season, the Mariners are undefeated at 7-6. He also has a K/BB ratio of 3.7. Castillo has been excellent for the Mariners and a key piece of why their pitching staff has been great as a unit. This is a difficult matchup against a Royals offense that has played great this season as well.

The Mariners have talent on offense, but they have struggled across the board this season. They are 29th in batting average at .220 after finishing last season at .242. Julio Rodriguez, Cal Raleigh, and Ty France lead the Mariners in most batting categories. Rodriguez leads the way in batting average at .266 and total hits at 67. Raleigh then leads in home runs at 11 and in RBI at 33. Ty France then leads in OBP at .319. This matchup against Marsh will be difficult because he has been having a great year pitching so far.

Why The Royals Will Cover The Spread/Win

The Royals have played well to start the year with a 37-26 record. Their pitching is a top-10 unit, while their batting has also been a top-10. Seth Lugo has made a potent pitching combination with Brady Singer, Alec Marsh, and Cole Ragans. Their bats have been red-hot recently. Salvador Perez and Bobby Witt Jr. have been the main standouts for the Royals behind the plate, but Maikel Garcia and Vinnie Pasquantino have also played well. The Royals have been one of the bigger surprises this season and are not slowing down against the Mariners.

The Royals are starting Alec Marsh on the mound. He has a 4-3 record, a 3.76 ERA, and a 1.15 WHIP on the year up to this point. Through 55 innings, he has allowed 24 runs on 46 hits with 17 walks and 46 strikeouts. He has started in 10 games so far this season and the Royals are 7-3 in those games. Marsh has been a key piece of the Royals' pitching staff and gets a favorable matchup against the Mariners' offense and their struggles.

The Royals offense has been red-hot after an initial slow start. They are seventh in team batting average at .253 after finishing last season with the same average. Their offensive output has been led by Salvador Perez and Bobby Witt Jr. in almost every batting category. Witt Jr. leads in batting average at .317, in home runs at 11, in RBI at 46, and in total hits at 80. Perez then leads the way in OBP at .379. The Royals have played great offense this season, but they get a tough matchup against Luis Castillo on the mound for the Mariners in this game.

Final Mariners-Royals Prediction & Pick

The Mariners are winning games despite their offensive struggles thanks to their pitching. The Royals have the better combination of pitching and offense in this game and they are at home too. Castillo is better than Marsh, but the Royals have more to like overall. Expect the Royals to cover and win at home against the Mariners.

Click here for more betting news and predictions

Final Mariners-Royals Prediction & Pick: Royals +1.5 (+116)