Shared trust is critical to Andre Agassi succeeding as Novak Djokovic's coach, says Tennis Channel analyst James Blake.

In a conference call with the media to promote Tennis Channel's Roland Garros coverage, which begins with this week's qualifying, Blake said the champions can click if they can communicate.

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"If you have a great relationship, you're going to be able to find a way to make it click with them," Blake told the media. "If you have all the information in the world, but you can't convey it to your player, you're not an effective coach. So it's tough for me to say.

"I think on paper, that makes a ton of sense. Andre has had every experience known to any tennis player, including winning the French Open, including have tough times in the middle of his career, being No. 1 in the world, being under intense scrutiny, pressure, all that kind of stuff that Novak and he can talk about. You would think they'd be perfect. But that's on paper."

Blake toppled world No. 1 Roger Federer at the 2008 Beijing Olympic Games before bowing to Djokovic in the bronze-medal match.

While Blake believes the analytical Agassi can be a major asset to Djokovic, he also expects a "trial-and-error" period as they learn about each other.

"Sometimes things don't work out. From the outside looking in, I love the relationship," Blake said. "Both those guys are great guys, very cerebral, amazing with scouting reports, the X's and O's of players they're playing against. I would think it's going to work out well.

"But that's also not knowing how long they've known each other, how long they've gotten to kind of feel each other out. I do think it's difficult if it happens hastily, and Andre doesn't know how to be effective with Novak.

Knowing when to speak is sometimes as important as the information coaches convey, Blake said.

"Players are individuals," Blake said. "Some players love getting a ton of information right before they go on the court. Some players hate that. They may need to do a bit of a trial and error period to figure out what works. They're both great champions, but both may have very different idiosyncrasies, just quirks that they do before a match, the night before a match.

"There may be a feeling out period for them. I hope that's not a trial and error in the middle of Roland Garros. I hope they've already talked about that. If they have, I think they're going to hit the ground running and be off to an unbelievable start."

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