The Royals have the third-worst record in the American League at 42-64. They have lost seven of their last 10 games. They also are 3-7 the past 10 times hosting Boston.
The Red Sox are the superior team. Boston got better at the trade deadline while the Royals got worse dealing their leadoff hitter Whit Merrifield.
The reason the Red Sox are cheaply priced here is they are starting rookie Josh Winckowski. He'll be facing Zack Grienke.
Winchkowski's overall numbers aren't good. But he did have a respectable outing in last start, holding the Brewers to two runs in five innings five days ago.
Greinke is just an innings-eater at this late stage of his once great career. His July ERA in five starts was 4.50. He has a 4.41 ERA on the season. Greinke doesn't have a good track record versus Boston with a 2-5 mark and 5.09 ERA in nine career appearances, including eight starts.