Yamaguchi Akane brushed off Clara Azurmendi 21-7, 21-11 to launch her India Open campaign in style on Wednesday (18 January).
Badminton's world female No. 1, who won last week's Malaysia Open to start the 2023 season, needed 25 minutes to get past her Spanish opponent in New Delhi.
Yamaguchi led from start to finish in the first game, winning 10 of the last 13 points from the interval as Azurmendi looked well out of it.
Azurmendi took the first two points of the second period but it was only a matter of time before Yamaguchi got going, the two-time defending world champion quickly opening up a commanding 14-6 lead to all but put the match to bed.
Other world number 1 players came out winners as well.
In the mixed doubles, Zheng Si Wei/Huang Ya Qiong beat Goh Soon Huat/Lai Shevon Jemie 21-11, 21-7 while in the men's doubles Fajar Alfian/Muhammad Rian Ardianto won 21-17, 21-16 over the Republic of Korea duo Choi Sol Gyu/Kim Won Ho.
The Malaysia Open was only the second time in history - the first since the 2018 Denmark Open - that the world No. 1 in all five disciplines topped the podium.
Men's singles first round selected results - India Open 2023
In the men's draw, third seed and former World champion Loh Kean Yew of Singapore came back from a game down to defeat Naraoka Kodai of Japan 18-21, 21-9, 21-7 in almost one hour of play.
Number two seed Lee Zii Jia also struggled in his opener. The Malaysian eventually came from a game down to beat Shesar Hiren Rhustavito of Indonesia 20-22, 21-19, 21-12.
World number one Viktor Axelsen beat Kidambi Srikanth of India in straight games. 21-14, 21-19 the score.