LOS ANGELES -- It’s hard to find anything wrong with winning a division title by 20 or so games, just as long as it doesn’t mean the Dodgers peaked too soon.

That’s always the default suspicion when the win rate tails off, particularly in the wake of a 4-2 loss to the last-place Rockies on Saturday night that snapped Colorado’s Dodger Stadium losing streak at 12.

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Despite a total of 99 wins, the Dodgers are only one game above .500 since Sept. 4, two games above .500 since Aug. 22 and three games above .500 since Aug. 16. They still haven’t secured home-field advantage through the National League Championship Series and trail the Yankees and Astros for that advantage should they return to the World Series.

Walker Buehler (13-4) took the loss against the team he beat to win the division last year in Game 163. Buehler, who has one more start before the postseason, was charged with four runs on five hits (two homers) and three walks in six-plus innings. It was his first loss since Aug. 15 at Miami. The Dodgers had won each of Buehler’s previous five starts and each of his previous six starts against the Rockies.

“Our execution is a little bit short right now,” said manager Dave Roberts. “This is where guys really need to ramp up and focus and really make pitches.”

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The Dodgers are giving plenty of rest to the weary and injured, while extending runways to rookies and sorting through an unsettled pitching staff. They’ve cut short starts, deployed bullpen games, generally conducted a simulated Spring Training when other clubs are battling down the stretch.

“You’re trying to check boxes and get guys prepared for what potentially is to come,” said Roberts. “But you’re still trying to win a baseball game, and I think we’re putting our best foot forward.”

Roberts used relievers Julio Urias, Pedro Baez, Kenta Maeda (back-to-back for the first time this year) and Adam Kolarek -- all likely to be in the postseason bullpen.

“We’ve done some things differently,” said Russell Martin, a veteran of nine playoff teams but never one that clinched so early. “We’ve saved some pitch counts, we had some bullpen days, had guys go in situations to prepare for the postseason, make sure guys come out of the ‘pen in situations.

“These games probably aren’t as important as today’s Cubs-Cards game, there isn’t that same feel. But you still play to win and everybody wants to win every single time. But we are ready to get going.”

This game, for example, served as a Major League rehab assignment for Justin Turner, who made his first start since spraining an ankle ligament two weeks ago. He went 0-for-2 before calling it a night after three innings, but said he felt fine and is expected to try it again on Sunday.

Max Muncy was out of the lineup with a tight left quad, but could return on Sunday. Without both, the Dodgers managed only one single over the final five innings. Martin drove in one of the runs, Corey Seager the other on a triple that center fielder Sam Hilliard missed on a dive.

Martin also made the tag at the plate on Raimel Tapia, who was cut down by center fielder Enrique Hernandez trying to score from second base on Hilliard’s single to end the eighth inning.