Alex de Minaur maintained his perfect round-robin record at the Next Gen ATP Finals.

The top-seeded Aussie believes the event's coaching rule is an imperfect policy.

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De Minaur needed just 61 minutes to dismiss Casper Ruud 4-1, 4-0, 4-2, to charge into his second straight Next Gen Finals semifinal.

One of the Next Gen ATP Final's rules innovation permits players to talk to their coaches via headset on changeoevers.

While de Minaur concedes the rule can provide tactical insight for fans, he doesn't like it.

"It's a tough question, that one, because I know that there is a fine line between tennis as being sort of an athlete's sport or a spectator's sport," de Minaur told the media in Milan. "I know that coaching is great for the spectators, as it gives insights on what the player is thinking and how to solve solutions.

"But me, as an athlete and a player, I don't actually like it. You know, that's just me, my opinion. I'm sure there is a lot of people who like it and a lot of people who don't, but this is my opinion of coaching."

The 18th-ranked Aussie said time will tell if any of the tournament's innovations, including coaching, no-ad scoring and sets to 4 games, will eventually translate to the main ATP Tour.

"I think obviously they are doing some great things with trying new rules and innovations here in Milan, and it will be a matter of time to see if any of these stick or we come up with new ideas," de Minaur said.

Photo credit: Mark Peterson/Corleve