To say they are polar extremes would not be an exaggeration.
The Red Sox own the best record in the majors at 59-29. They have won eight of their past 10 and 10 of their past 13. They are 30 games over .500 for the first time since they ended the 2013 season 32 games above.
Boston leads the American League with 463 runs and has outscored its opponents by 130 runs.
On the flip side, the Royals have lost six straight, 18 of 21 and 25 of 30. They are 25-61 and are 36 games below .500 for the first time since ending the 2006 season 62-100.
Kansas City ranks last in the American League with 297 runs and has been outscored by 167 runs.
"We didn't have opportunities to manufacture runs," Royals manager Ned Yost told reporters after Wednesday's 3-2 loss to the Cleveland Indians. "We had opportunities with runners in scoring position that we couldn't capitalize on. And that's been a major problem for us all year long."
The Red Sox are 31-17 on the road. The Royals have lost 12 of their last 13 games at Kauffman Stadium and their 11-32 home record is the worst in the majors.
The Royals have not scored more than four runs in 25 of their last 26 games. They have failed to collect double-figure hits in 25 of their last 26 games and are batting .191 with 55 runs in that stretch.
And who do the Royals face in the opener of this series?
None other than dominant left-hander Chris Sale, who leads the American League with 164 strikeouts and is averaging 12.7 strikeouts per nine innings. Opponents own a .179 batting average versus Sale (8-4, 2.41 ERA).
"He looks like the best pitcher in the big leagues right now," Boston manager Alex Cora said.
Sale, who ranks among the league leaders in overall ERA, owns a 2.32 road ERA and a 2.45 night ERA. He enters the game having not allowed a run in his past 15 innings. Sale is 3-1 with a 1.03 ERA in his past five starts after striking out and allowing a first-inning single to Giancarlo Stanton in seven dominant innings in an 11-0 win at Yankee Stadium over the New York Yankees on Saturday.
"He was outstanding again," Cora said. "Fastball command and off-speed pitches, it was a great performance."
Sale is 10-10 with a 2.92 ERA in 33 career appearances, 22 starts, against Kansas City. He held the Royals to two runs and five hits while walking two and striking out six over seven innings in a no-decision on May 1 at Fenway Park. Sale is 2-0 with a 2.87 ERA in his last four starts in Kansas City, striking out 34 and walking five.
The Royals will counter with right-hander Jason Hammel, who is 2-10 with a 5.56 ERA. He is tied for the AL lead in losses and has yielded 15 runs in his last two starts. He is 0-5 with a 4.33 ERA in seven home starts this season.
Against the Red Sox, Hammel is 3-4 with a 5.13 ERA in 16 career appearances, nine of them starts. He dropped a 10-6 decision on April 30 to Boston, allowing eight runs on eight hits, including a pair of home runs, and three walks over 4 2/3 innings.
While Sale was the AL Pitcher of the Month for June, Hammel went 0-5 with a 6.43 ERA in six starts last month after ending May with back-to-back victories.
Hammel's biggest challenge will be Mookie Betts and J.D. Martinez. They rank 1-2 in the majors in slugging percentage with Betts at .669 and Martinez .642.
Betts has 21 home runs and a .338 batting average. Martinez is hitting .327 with a major league-best 26 home runs, which is more than any Boston player hit in 2017.
Betts also hit three homers at Fenway Park on May 2 and went 4-for-4 in that game.