Kansas City Royals vs St. Louis Cardinals Prediction, Odds and Picks for Today, 05/15/26

It is interleague rivalry weekend across the league, and that takes us to the Show Me State for the Kansas City Royals vs. the St. Louis Cardinals. The Royals are in poor form, having just been swept by the White Sox and losing 4 in a row. That is despite the best efforts of Bobby Witt, who efficiently gets on base but seems to be playing alone most nights. The Cardinals split with the Padres and Athletics on a west coast swing, and they have been one of baseball’s pleasant surprises this season. Most signs would point to the Cardinals on Friday, so I am going to go the other way and back the Royals.

The pitching matchup should be a solid one, as Michael Wacha and Dustin May face off. Wacha has tossed 2 straight 7-inning gems for KC, while Dustin May has recorded 5 quality starts in his last 6 outings. These teams need their starters because both bullpens have been gross, as they rank 5th and 6th-worst in ERA. Heading back from a west coast trip and playing the next day is often a sluggish spot though, so I will go against St. Louis and take Kansas City to sneak in a win here.

Royals vs Cardinals Prediction: KC Royals ML (-110) available at the time of publishing. Playable to -115.

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