"Today was my birthday, so maybe that took a little bit of the stress off," Anisimova, who turned 25, told reporters after her victory in Flushing Meadows, where the crowd sang her "Happy Birthday."
Anisimova fought off three break points early for a 2-1 lead before running away with the opening set in the all-American matchup at Louis Armstrong Stadium.
The players traded breaks to open the second set but Anisimova, the world number 10, never let her grip on the match slip, breaking Krueger's serve in the final game to win the match in one hour and 12 minutes.
"Ashlyn was playing some great tennis, so I feel like the quality and the level was pretty high today," Anisimova said.
"I think everyone is always nervous for the Grand Slam first round because you're trying to find your tennis and maybe find your rhythm, because first rounds don't always necessarily have the highest quality," she added.
"I felt great out there today. I thought I played well. So I'm happy about that."
Anisimova will face Austrian Lilli Tagger in the second round.
