Naomi Osaka, happy to play for a crowd, wins her first-round match.

Naomi Osaka had a solid start to the defense of her U.S. Open title, posting a 6-4, 6-1 win over Marie Bouzkova of the Czech Republic that was a little closer than the final score suggested.

Osaka and Bouzkova were dead even through a hard-fought first set filled with tight games, long points and hard-hitting rallies. In the 10th game, Osaka finally forced Bouzkova into a backhand error on her third set point to take the lead with her first service break and claim the opening set.

Osaka seemed to settle in from there, jetting to a 5-0 lead in the second set before Bouzkova was finally able to hold her serve. Osaka finished Bouzkova off in the next game with a forehand winner down the line that caught the edge of the paint.

This was a far different atmosphere than anything Osaka experienced on her march to the championship last year, when no spectators were allowed at the tournament. She played Monday at Arthur Ashe Stadium in front of nearly 20,000 fans who were loud all night and have begun to embrace her as one of their own. Osaka was born in Japan and represents that nation but grew up largely in New York and Florida.

“It feels kind of amazing to play in front of everyone again,” Osaka said after the match, “The energy here is unmatched.”