TOKYO -- Shohei Ohtani seems impervious to a variety of conditions that afflict most humans -- nerves, anxiety, distraction -- but it took playing a regular-season big-league game in his home country to change all of that.

After the Los Angeles Dodgers' Opening Day 4-1 win over the Chicago Cubs in the Tokyo Dome, Ohtani made a surprising admission. "It's been a while since I felt this nervous playing a game," he said. "It took me four or five innings."

Ohtani had two hits and scored twice, and one of his outs was a hard liner that left his bat at more than 96 mph, so the nerves weren't obvious from the outside. But clearly the moment, and its weeklong buildup, altered his usually stoic demeanor.

"I don't think I've ever seen Shohei nervous," Dodgers manager Dave Roberts said. "But one thing I did notice was how emotional he got during the Japanese national anthem. I thought that was telling."

As the Dodgers began the defense of last year's World Series win, it became a night to showcase the five Japanese players on the two teams. For the first time in league history, two Japanese pitchers -- the Dodgers' Yoshinobu Yamamoto and the Cubs' Shota Imanaga -- faced each other on Opening Day. Both pitched well, with Imanaga throwing four hitless innings before being removed after 69 pitches.

"Seventy was kind of the number we had for Shota," Cubs manager Craig Counsell said. "It was the right time to take him out."

The Dodgers agreed, scoring three in the fifth inning off reliever Ben Brown. Imanaga kept the Dodgers off balance, but his career-high four walks created two stressful innings that ran up his pitch count.

Yamamoto rode the adrenaline of pitching in his home country, routinely hitting 98 with his fastball and vexing the Cubs with a diving splitter over the course of five three-hit innings. He threw with a kind of abandon, finding a freedom that often eluded him last year in his first year in America.

"I think last year to this year, the confidence and conviction he has throwing the fastball in the strike zone is night and day," Roberts said. "If he can continue to do that, I see no reason he won't be in the Cy Young conversation this season."

Cubs right fielder Seiya Suzuki went hitless in four at bats -- the Cubs had only three hits, none in the final four innings against four relievers out of the Dodgers' loaded bullpen -- and rookie Roki Sasaki will make his first start of his Dodger career in the second and final game of the series Wednesday.

"I don't think there was a Japanese baseball player in this country who wasn't watching tonight," Roberts said.

The Dodgers were without Mookie Betts, who left Japan on Monday after it was decided his illness would not allow him to play in this series. And less than an hour before game time, first baseman Freddie Freeman was scratched with what the team termed "left rib discomfort," a recurrence of an injury he first sustained during last year's playoffs.

The night started with a pregame celebration that felt like an Olympic opening ceremony in a lesser key. There were Pikachus on the field and a vaguely threatening video depicting the Dodgers and Cubs as Monster vs. Monster. World home-run king Saduharu Oh was on the field before the game, and Roberts called meeting Oh "a dream come true."

For the most part, the crowd was subdued, as if it couldn't decide who or what to root for, other than Ohtani. It was admittedly confounding: throughout the first five innings, if fans rooted for the Dodgers they were rooting against Imanaga, but rooting for the Cubs meant rooting against Yamamoto. Ohtani, whose every movement is treated with a rare sense of wonder, presented no such conflict.