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The Cubs opened a six-game road trip Friday night with a difficult task — right-hander Yoshinobu Yamamoto and the Los Angeles Dodgers.

It was an old-fashioned pitcher’s duel, as Yamamoto and Cubs left-hander Matthew Boyd kept the offenses at bay through five innings. Ultimately, the Dodgers prevailed with a three-run sixth inning that produced a 3-0 series-opening win at Dodger Stadium.

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Here are three takeaways as the Dodgers improved to 11-4 over the Cubs, who fell to 9-7:

Boyd’s bane

Boyd went toe-to-toe with Yamamoto through 5.1 innings.

But, man, this Dodgers lineup is so good that they can turn things around quickly — as they did in the sixth.

Teoscar Hernández hit a one-out single, and Boyd hit Freddie Freeman with a pitch one batter later to put the go-ahead run in scoring position in a scoreless contest.

Tommy Edman, who might have to be officially classified as a “Cubs Killer,” needed only one swing to boost the Dodgers. He crushed a 79.8-mph Boyd changeup 423 feet into the left field bleachers to make it a 3-0 ballgame.

In a pitcher’s duel, that felt like a 30-run homer.

Edman has hit .333 with six home runs and 11 RBI for a 1.333 OPS in six games against the Cubs since joining the Dodgers last season.

It was a sour note to what had been another solid outing by Boyd, who signed a two-year deal in the offseason and has turned out to be a solid addition. The mighty Dodgers lineup couldn’t do much against Boyd through their first 16 outs of the game.

LA mustered just four men on base through the first five innings — two walks and two singles — and didn’t have a runner reach second until the sixth. But the slightest mistakes quickly can be magnified against the Dodgers, as they showed.

Yamamoto deals

Boyd had to be so good because his counterpart was dominant.

Yamamoto retired the first nine batters he faced, then worked around one-out Kyle Tucker double in the fourth. The Cubs had no answer for the right-hander, who struck out nine in six innings.

The 26-year-old — like his compatriot, Cubs lefty Shota Imanaga — heavily relies on a fastball-splitter mix, and that worked to his strength Friday. He threw the four-seam 36 percent of the time and the splitter 30 percent. The Cubs whiffed seven times on the splitter.

The Cubs entered with the second-best walk rate (12.7 percent) in baseball and the fifth-lowest strikeout rate (19.1 percent). They mustered one walk to the nine punchouts against Yamamoto.

This one game doesn’t suddenly mean the Cubs are a swing-happy, strikeout-heavy offense. They faced one of the game’s best arms and had a rough go of it. That will happen, but they must make the most of any limited opportunities in those contests …

Baserunning gaffe

… Like the one they had in the fourth inning.

Yamamoto was cruising, but Tucker hit a one-out double down the right-field line to put pressure on the righty.

Seiya Suzuki followed with an opposite-field single. Cubs third base coach Quintin Berry held Tucker up at third, but Suzuki rounded first and went for second, assuming Tucker would be sent. Suzuki was caught in a rundown for the second out, and Yamamoto struck out Michael Busch to wiggle out of the jam.

Listen, one run isn’t enough to win a baseball game most nights. But in a pitcher’s duel like this one, when scoring is at a premium, those runs — and consequently, those outs — must be treasured. Instead, Suzuki gave Yamamoto a much-needed free out.

The Dodgers ended up scoring three runs two innings later, so the one run probably wouldn’t have been enough. But if the Cubs could have scored that run or even multiple with runners at the corners and one out, it might have changed how Boyd attacked hitters, especially in that decisive sixth inning.

Suzuki’s mistake was a rare one — baserunning has been a team strength early this season — and makes it that much harder of a pill to swallow.