The Cincinnati Reds made the most of their first experience with baseball’s new extra-inning rule.

Nick Senzel, who made the last out in the ninth inning, started the 10th inning on second base. After Nick Castellanos walked, a double to deep center field by Joey Votto scored Senzel as the Reds beat the Kansas City Royals 6-5 in the opener of a two-game series Tuesday at Great American Ball Park.

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“To have speed at second base, that played into it tonight for sure,” Reds manager David Bell said. “Great at-bat by Nick Castellanos, and Joey just comes through like he has so many times throughout his career. Big hit for us as a team.”

Baseball instituted the extra-inning rule, which has been used in the minor leagues the last two seasons, to help teams deal with the shortened season. Each half inning starts with a runner on second base. That runner is the player who made the last out in the previous inning, though teams can sub in a player at that spot.

“Welcome to 2020, I guess,” said Reds shortstop Kyle Farmer. “Everything’s out the window. As a player, I enjoyed (the new rule).”

The Reds improved to 8-9 in the 60-game series. They have won three of their last four games. They trail the first-place St. Louis Cardinals by 4½ games in the National League Central Division. The top two teams in each division and the two teams with the next best record in each league qualify for the 16-team playoffs.

Farmer got the Reds on the board with a two-run double in the second.

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A two-run home run by Matt Davidson and a solo home run by Jesse Winker extended the lead to 5-1 in the third.

Luis Castillo allowed one earned run in six innings for the Reds, who committed three errors and allowed two unearned runs when Castillo was on the mound.

The Reds led 5-3 when Amir Garrett gave up a game-tying two-run home run to Ryan McBroom in the eighth.

Lucas Sims earned the victory by pitching a scoreless 10th. He walked a batter but stranded the leadoff runner Hunter Dozier at second base.

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