KANSAS CITY, MO. – The Twins won something they don't care much about Saturday. But they lost something that matters a great deal to them.

Luis Arraez was injured in a collision with Willians Astudillo while they tracked a popup near the mound, falling in obvious pain and grimacing as he held his right leg. Arraez was eventually driven off the field in a cart for tests, and the results were both good and bad.

The rookie infielder broke no bones nor suffered any injury to his knee or ligaments, the Twins believe, but he suffered a sprained ankle as he landed, the tests showed. He was on crutches in the clubhouse after the 4-3 victory over Kansas City, and hobbling badly without them, putting his participation in the AL Division Series in serious doubt.

With six days before the playoffs begin, manager Rocco Baldelli said, "there's no real reason for us to speculate" about whether he can recover in time to face the Yankees. "We play on Friday, so we have some time to figure it out."

For a team that is already worried about the health of Max Kepler and Marwin Gonzalez, it's the worst possible outcome of a game that Baldelli candidly admitted mattered little to the Twins.

"We'll still go out and compete, and do our best," Baldelli promised before the game. "But having that slight mental break, not having to really live and die by the end result of the game, is really helpful."

Not if competing hard means important players will sit out the playoffs. It's too soon to tell whether that is the case with Arraez, but his injury overshadowed the Twins' sixth consecutive victory and 101st on the season.

With Hunter Dozier batting in the seventh inning, Tyler Duffey threw a 1-2 fastball that Dozier popped almost straight up. All four Twins infielders converged near the mound, and Duffey suddenly ducked and ran off the back of it. Astudillo, playing first base, settled under the ball on his side of the mound, but Arraez, coming in from third base, was running at top speed with his eyes in the air.

"The ball was hit really high. I heard [Astudillo], so I kind of checked where everybody was, and shot the gap," Duffey said. "Arraez, coming from third, he had a little momentum coming in, and couldn't slow down quick enough."

The infielders collided, and Arraez spun around. His right foot landed awkwardly, and Astudillo stepped on it as both dropped to the ground. Arraez held the back of his right leg as he laid on the grass, and Baldelli and head athletic trainer Tony Leo hustled to the mound to attend to the 22-year-old Venezuelan. A cart was eventually brought out, and Arraez was driven off the diamond through the Royals bullpen, headed for medical treatment.

"He was definitely scared at the time, and I don't blame him," Baldelli said. "It's nobody's fault. There were a lot of people in a very small space, and the height of the popup probably just forced everyone to kind of rush over there at the same time."

Arraez is hitting .334 in 92 games as a rookie and almost certainly was a lock to be a regular starter for the Twins this postseason.

"It's difficult. He's a huge part of the team. Definitely, we're a better team when he's playing," said Nelson Cruz, who broke a 3-3 tie in the eighth inning by blasting home run No. 401 of his career into the seats in deep left-center off Jacob Barnes. "He's a great kid. We love him. He's always willing to help and learn."

Jorge Soler homered twice to pass Mike Trout and will become the first Royals player ever to win the AL home run title. He hit his 46th in the first inning off starter Cody Stashak, and his 47th, a two-run shot in the seventh, tied the score and ended Duffey's scoreless streak at 23⅔ innings, dating to July 23.

But what happened one batter later was of more immediate concern to the Twins.