One team is a virtual lock while the other is a long shot for the postseason. It would be tough to guess which is which by looking at the last week-and-a-half for the Kansas City Royals and Cleveland Indians.

A September slide has the first-place Royals out of sorts, but they look to end their skid against the wild card-hopeful Indians on Tuesday night.

Kansas City (84-59) is all but guaranteed to win the AL Central but has scuffled with eight losses in 10 games. Meanwhile, Cleveland (71-71) has nestled back into the wild-card conversation with wins in six of eight.

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Those trends continued with the Indians' 8-3 victory Monday, dropping the Royals' division lead to nine games over Minnesota -- single digits for the first time since Aug. 7.

"It's not a horribly long time, eight out of 10," manager Ned Yost told MLB's official website. "But it's like getting the flu. You got to let it run its course. Once it runs its course, you're fine."

The Indians have been better than fine since Aug. 20 with one of the best records in the majors at 16-7, and they sit 4 1/2 games back of Texas for the second wild card. Cleveland will try to move above .500 for the first time since it was 2-1.

Josh Tomlin has played a key role in the resurgence after spending the first 4 1/2 months of the season on the disabled list following right shoulder surgery. Since a loss in his return on Aug. 15, the right-hander has won five straight starts behind a 2.86 ERA.

Tomlin (5-1, 2.85 ERA) ranks toward the top of MLB with 10 home runs allowed since his return, but nine of them were of the solo variety. He has four quality starts, including a four-hitter.

Tomlin gave up three solo home runs in 5 2/3 innings of a 6-4 win over the Chicago White Sox on Wednesday. Eleven of Tomlin's 13 runs allowed since his return were via the long ball, but Kansas City ranks toward the bottom of MLB with 119 home runs.

"That's an issue that I'm trying to correct," Tomlin told MLB's official website. "But I'm never going to shy away from contact from guys."

Tomlin is 1-2 with a 6.97 ERA in his past four starts against the Royals. Salvador Perez leads a group of Kansas City hitters who have fared well against him with seven hits in nine at-bats, including a homer and two doubles. Mike Moustakas (5 for 12, two home runs), Lorenzo Cain (4 for 8), Alex Rios (5 for 11) and Alex Gordon (9 for 31, three doubles) have also had success.

Kansas City's disappointing 10-game stretch began with a loss from scheduled starter Kris Medlen.

Medlen (3-1, 4.58) has been good in three starts and terrible in the other since coming out of the bullpen to take Jeremy Guthrie's spot in the rotation three weeks ago.

The right-hander won his first two before the White Sox reached him for seven runs and 11 hits over 5 2/3 innings of a 12-1 defeat on Sept. 2. Medlen rebounded with his best start on Wednesday, taking a no-hitter into the sixth before allowing two runs and three hits in his final inning of a 12-inning, 3-2 loss to Minnesota.

He's 8-2 with a 2.21 ERA in 23 career appearances in September.