The trial, which began last month, allows an individual to coach a player both verbally and non-verbally from a designated seat provided that it does not interrupt play or hinder an opponent.
The trial will include the US Open and run through to the season-ending ATP Finals in Turin in November before the ATP evaluates whether to allow it on the Tour in future.
The WTA Tour also has an off-court coaching trial in place.
"During the match, I don't really see how a coach can help," US Open champion Medvedev told reporters. "In some other sports there is tactics, it's so important.
"When a tennis match is there, I guess it can be one match out of five where suddenly he's going to be like, 'change your position on return', or, 'go more to his backhand', if he sees it from the outside."
On Wednesday, August 17th, American Taylor Fritz (24) said that allowing players to receive instructions during a match was a "dumb rule" that went against the concept of tennis being an individual sport.
Medvedev meets Fritz on Friday, August 19th, for a place in the semi-finals of the Cincinnati Open.
"Let's say I play Fritz tomorrow, it's our first encounter, still I know how he plays and he knows how I play. I don't think on-court coaching tomorrow is going to make a huge difference," said the Russian.
"But in general, I'm okay with it, like I was never against it."
