Elastic athleticism and eye-popping quickness are assets Novak Djokovic applied completing the career Grand Slam last June.

New coach Andre Agassi says he's most surprised by the depth of Djokovic's mind.

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"I’m shocked at what a fast learner he is," Agassi told Barbara Schett-Eagle in a Eurosport interview on Facebook Live. "Coaching is not just saying information, you have to learn and then somebody has to believe and have the ability to apply it. That takes a lot of trust and he’s a very trusting person. Every day I’ve seen him get better."

The 1999 Roland Garros champion said Djokovic's game is so strong it would cause him sleepless nights and impresses him so much he's coaching for free.

"If you gave me his game, the hardest part about winning this tournament would be going to sleep at night," Agassi told Schett-Eagle. "Because I’d be so excited to come here tomorrow to play...

"I respected his search for finding new solutions. He’s a very inspirational person. He’s got a high IQ, a high tennis IQ, a high emotional IQ. I do it on my time and on my dime because he’s worth caring about and he’s important to the game."

The 47-year-old Agassi said he's not a full-time coach and isn't being paid as the pair get to know each other and come to an agreement on scheduling.

"I’m doing this because I feel inspired to help this guy," Agassi said. "I’m not accepting it as a job. I’m not accepting it as payment. I am truly committed to making sure that he can be at his very best.

"How achievable it is to be with him at tournaments is gonna vary a lot because I have a lot of responsibilities. The good news is I don’t think he needs a whole lot. We’ll figure it out and I will be there for him how he needs be to be. That we’re figuring it out more and more every day."

Djokovic initially approached Agassi about his availability during the Monte Carlo tournament in April. The Hall of Famer said coaching has been a learning experience as he focuses on daily improvement.

"You can see a lot in a person’s eyes," Agassi said. "I’m learning how he processes, I’m learning what’s important to him. I’m learning what information he needs and what information he has that might not be ideal.

"You look at these things and you try to understand somebody. And then you try to fill in the pieces that can help him take a step every day."

Photo credit: Roland Garros