"It's kind of a transition time for the ATP, but, yeah, I think there is a lot of talent coming up."
Shapovalov is one of a number of young guns making their way through the ATP ranks.
Russia's Andrey Rublev, who faces Bosnia Herzegovina's Damir Dzumhur for a place in the fourth round, is another, as is Frances Tiafoe of the US.
Even in defeat, the young guns have left an impression.
Tiafoe left the crowd breathless when he took five-time US Open champion Federer to five sets before surrendering in the opening round.
"Every Grand Slam, it's a chance for young guys to prove themselves and I have been doing that," said Shapovalov, who will take on 12th-seeded Spaniard Pablo Carreno Busta for a spot in the quarter-finals.
"Hopefully I can keep doing that. Guys like Rublev or anyone else [are] still in, why not?
"I think everyone is beatable."
Earlier, former champion Marin Cilic's campaign ended after the Croatian fifth seed was beaten 4-6 7-5 7-5 6-4 by Argentine counter-puncher Diego Schwartzman.
Cilic, who skipped US Open warm-up tournaments in Montreal and Cincinnati due to injury, hit 80 unforced errors in an untidy display. Schwartzman will now take on either France's Lucas Pouille or Kazakh Mikhail Kukushkin for a quarter-final spot.
• In the women's draw, Maria Sharapova fought off the challenge of American teenager Sofia Kenin to reach the fourth round with a 7-5 6-2 victory.
After three-set struggles against Simona Halep and Timea Babos in earlier rounds, this was slightly more comfortable for Sharapova.
The five-time grand slam champion next plays 16th seed Anastasija Sevastova.
"We've never faced off against each other before, she's up and coming, she had nothing to lose and that's always dangerous," Sharapova said.
"I didn't see the ball too well at the beginning, made a lot of unforced errors. But ultimately what matters is I won."
Playing her third match on Flushing Meadows' centre court and second in the prime-time night session, Sharapova did not have the crowd with her this time as they got behind Kenin.
The Russian-born teenager had never won a grand slam match before this week and, unless she turns professional immediately, will have to forfeit her US$144,000 ($201,000) in prize money. Petra Kvitova returned to the US Open's big stage and delivered a sizzling performance by blowing past French 18th-seed Caroline Garcia 6-0 6-4 to reach the fourth round.
Kvitova, playing in just her eighth tournament since missing five months of action after being stabbed in the hand last December, dispatched Garcia within 73 minutes in Arthur Ashe Stadium, closing out the contest in style with an ace.
"It means a lot, I really appreciate it that this time I could play again on the big stages," said Kvitova.
"After everything that I have been through, it is a very happy moment for me."
- AAP