The Laver Cup completed it’s second successful event in Chicago this year as Europe defended their title against the Rest of the World.
However, questions hang over the future of the tournament as the exhibition event takes place towards the end of the season.
Several players have complained over the last month of the tennis schedule already being too congested.
“What’s Laver Cup? Laver Cup is nothing,” Carbonell said.
“It’s a format that has success because its ultimate player competes in it, and wherever Federer goes, you have a packed crowd.
“But when he retires… What value does it have? Who will go to an exhibition?
“Without points, only for money… The ones who lived for tennis know that exhibition tournaments last less.”