French duo Harold Mayot and Valentin Royer made a mockery of rankings and past glory to ensure a blistering start to their respective ITF World Tennis Tour Junior Finals campaigns on the tournament’s opening day.

Current junior world No. 5 Mayot, fresh from his maiden Grade A triumph at Osaka at the weekend, produced an inspired display to overcome Czech Republic’s Jonas Forejtek, who is the top-ranked boy on the planet and winner of last month’s Junior US Open Tennis Championship, 6-1 6-3.

Royer followed suit on Centre Court, opening his Chengdu account in style by defeating Argentina’s Thiago Agustin Tirante – a player five places ahead of him in the freshly updated boys’ standings.

Victory was perhaps particularly significant for Mayot given the strength of Group Shuai, which contains a second Junior Grand Slam winner in the form of Denmark's Holger Vitus Nodskov Rune, who overpowered Chinese wildcard Yunchaokete Bu 6-4 7-6(4).

“This is a fantastic day,” Mayot, who plays Rune on Centre Court on Thursday, told itftennis.com. “It’s such an important victory because there are two Grand Slam champions in this group.

“It was a tough match but I tried to be aggressive and stay calm and I’m very happy with this win. It’s a great win but it is only the first match, so just the beginning, and there are tough matches to come. I have to produce a similar level, but this victory has given me plenty of confidence.”

Mayot and Royer are two of four French players competing in Chengdu. Newly-crowned girls’ No. 1 Diane Parry and Elsa Jacquemot are the others, with the former’s win over American Hurricane Tyra Black making it three wins for the French contingent on day one.

“It’s nice to have such a strong French presence here,” Royer told itftennis.com. “Harold is a really good player and he deserves his victory over Jonas today, and the success he is having. We all deserve it.

“I had a really good match. It was one of those days where you feel unbelievably good on court and everything goes for you. I’m really pleased with my level of play.

“I was quite tense earlier in the week and not playing well in practice. I spoke a lot with my coach to get relaxed and it paid off. I’m the type of guy who is going to hit strong and try to win points, I did today and I’m really happy.”

Royer is joined at the top of Group Yong by Japan’s Shintaro Mochizuki, who he faces on Court No. 1 on Thursday. Reigning Wimbledon boys’ champion Mochizuki ensured a positive start to his title tilt by beating Canada’s Liam Draxl 6-4 6-2.

Home favourite Zheng Qinwen, meanwhile, had the honour of raising the tournament’s curtain and playing first on Centre Court. She made the most of such a lofty status to dispatch Japan’s Natsumi Kawaguchi 6-2 6-4 following a rain delay. There was a poignancy to her early success.

“It is really special to play in China and to win here because my mum is from Chengdu, so I am half from Chengdu and that is a difference I have compared to the other players,” said Zheng, who will do battle with Black on day two. “I am really proud to have won my first match here.”

While Zheng and Parry are leading the way in Group Li, Wimbledon girls’ champion Daria Snigur and Latvia’s Kamilla Bartone are Group Liang's early frontrunners following victories over Jacquemot and Oksana Selekhmeteva respectively.

Ukraine’s Snigur was forced to recover from a set down against the youngest player in the girls’ draw Jacquemot, who only arrived in Chengdu on Tuesday afternoon following extensive travel delays, but eventually prevailed 4-6 6-3 6-2.

Bartone, meanwhile, insisted it was “very difficult to play against a great friend” after coming from behind to defeat doubles partner Selekhmeteva of Russia. Bartone will draw swords with Jacquemot on Thursday, while Snigur does battle with Selekhmeteva.