Maybe it's those eternally boyish looks that makes it easy to forget, but Alex de Minaur is no longer in that bracket of youthful tennis wannabes, the 'NextGen' brigade.
Instead, they're looking across the net at him.
On Thursday, de Minaur, now in his 10th full year as a hardened old stager on the ATP tour and very possibly in his prime at 25, will face arguably the best of the new teenage battalion when he tackles Jakub Mensik, in the last-16 of the Rotterdam Open.
Mensik, a 19-year-old Czech, is the only teenager in the world's top 50 and going places quickly, a clean-hitting 193cm powerhouse with a monster serve and a spectacular forehand.
He's been on an upward trajectory since he reached the third round of the US Open 18 months ago, getting to his first final in Doha last year and being recognised as the 2024 ATP Newcomer of the Year.
He started this year just as well by beating three-time grand slam finalist Casper Ruud in the Australian Open, one of five top-10 victims he's already toppled in his nascent career.
Tomorrow, he'll aim to make it six, and world No.8 de Minaur will know how difficult Mensik is to tame after having quite a job to subdue him in three sets in Vienna last October. The man from Prostejov appears to have improved since then too.
De Minaur, the third seed, has started the season really well, with eight wins and his only loss being that sobering lesson from Jannik Sinner in the Australian Open. He wasn't, of course, the only player to suffer being dismantled by the brilliant Italian there.
'Demon' hopes to go one better than reaching the Rotterdam final as he did last year (losing to Sinner) as the tournament reaches its business end.
The winner of their match will go on to face the victor between another young star, Frenchman Arthur Fils and German lucky loser Daniel Altmaier, in the quarters.
The 20-year-old Fils, who was de Minaur's opponent at Wimbledon when he suffered the hip injury that prevented him playing his quarter-final with Novak Djokovic, progressed on Wednesday with a 6-7 (4-7) 6-2 6-1 win over compatriot Constant Lestienne.
Elsewhere, Matteo Berrettini was beaten in three sets by local Tallon Griekspoor but fellow Italian Mattia Bellucci triumphed over second seed Daniil Medvedev, 6-3 6-7 (2-7) 6-3.
"I really tried to enjoy every minute of it," qualifier Bellucci, who earned his first top-10 win, said.
"I tried to have fun on court and be myself as much as possible. I hit the serve and volley a bit and hit the underarm serve ... This is a big result so I will enjoy it."
Hubert Hurkacz and Andrea Vavassori also progressed after their respective opponents were forced to retire.
