CHICAGO -- Having grown up in Kentucky, Dodgers right-hander Walker Buehler went into the visitors' clubhouse Saturday eager to watch what would unfold during the Kentucky Derby.

On Sunday night, it was the Dodgers’ turn to watch their horse dominate on the mound. Buehler allowed just one run and struck out six over seven innings in the Dodgers’ 7-1 win over the Cubs at Wrigley Field. It was the Dodgers’ first sweep over the Cubs in Chicago since August 2013.

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“He’s thrown the heck out of the baseball for us,” said Dodgers manager Dave Roberts. “Obviously we expect -- he expects -- to always be better and continue to get better. He’s been fantastic. Effective, efficient, logging innings and performing. So tonight was a good night.”

Buehler’s night didn’t start as planned, however, as he gave up a leadoff double and a two-out RBI single to Willson Contreras in the first inning. The right-hander, however, quickly settled in and took care of the Cubs’ offense.

A big reason for Buehler’s success on Sunday was his cutter. Buehler threw the pitch 38 times. As he no longer touches triple digits with his four-seamer, Buehler’s cutter has become his go-to pitch over the last year. His curveball was also efficient, getting five of his season-high 15 whiffs on the pitch.

“I think in this game you have to make adjustments, and throwing that pitch more was a big adjustment for me last year and especially trying to get lefties out,” Buehler said. “Now I’m trying to throw it more to right-handers than I have in the past and protect my slider. So it’s been good.”

Buehler made his 100th career start on Sunday and was able to display the growth he’s made over the last few seasons. He entered the league in 2017 as someone who was prepared to try and blow 100 mph fastballs past hitters.

As evidenced by Sunday’s performance, the All-Star pitcher doesn’t rely as much on his four-seamer anymore. Instead, he’ll turn to a plethora of other weapons. His focus has also shifted toward providing consistent length and not chasing high strikeout numbers.

It might look different for Buehler, but he continues to ascend into one of the best pitchers in the Majors. Among pitchers who made their debut since the mound was lowered in 1969, Buehler ranks fourth with a 2.70 ERA in his first 100 starts. His 0.99 WHIP as a starter is the lowest in a pitcher’s first 100 career starts since at least 1901.

“I think the thing with Walker is he’s such a student of the game,” Roberts said. “He’s learning the league, understanding hitters, understanding swings, and also really understanding how his pitch mix plays at this level. So you look back to when he first broke in to now, he’s just obviously so much more experienced. He’s just continuing to get better.”

Behind Buehler, the Dodgers’ lineup did more than enough to help the team get off to a 19-7 start this season. Mookie Betts extended his hitting streak to nine games with a pair of singles. Gavin Lux and Cody Bellinger got on base three times apiece.

Los Angeles’ lineup, which most expected would be the best in the Majors, leads the league in runs per game, and that’s despite some of its stars still battling through some struggles at the plate. Those stars are confident they will turn that around, but they haven’t had to do much given the Dodgers’ stellar pitching.

With Buehler and Clayton Kershaw leading the way, the pitching staff is off to one of the best starts in Major League history. The Dodgers have held their opponents to three runs or fewer in 22 of their first 26 games. The only other team in AL/NL history to have more such games through 26 contests is the 1907 Cubs, who went on to win the World Series.

“Even though we’re not hitting homers and doing all that we did tonight, we’re still scoring seven runs,” said Dodgers first baseman Freddie Freeman. “And Walker was unbelievable.”