Rafael Nadal issued a reality check to tennis' governing bodies.
The world No. 1 says two team events can't coexist successfully in a six-week span, therefore ATP Cup and Davis Cup should unify in one true tennis World Cup.
More: Djokovic Stops Nadal in ATP Cup
Nadal, who led Spain to the Davis Cup championship last November in Madrid, helped Spain reach the ATP Cup final on Sunday. Second-ranked Novak Djokovic beat Nadal for the eighth straight time on hard court then partnered Viktor Troicki to prevail in the decisive doubles lifting Serbia to the inaugural ATP Cup with a 2-1 triumph over Spain.
Afterward, Nadal said the two Cup competitions, which follow Laver Cup in September, clutter the calendar, can confuse fans and realistically cannot coexist in the long run.
"[The ATP Cup] is a long competition. It's a tough way to start the season," Nadal told the media in Sydney. "I don't know. I think it's a great competition but, at the same time, I can't change my mind.
"Two world cups in [over] one month is not real. It's not possible. So, we need to find a way to fix it and we need to find a way to make a big deal with ITF and ATP to create a big world team cup competition, not two world cups in one month. I think that's confusing for the spectators."
The 19-time Grand Slam champion called unifying the Cups a "mandatory" mission for the game's governing bodies.
"We need to be clear in our sport," Nadal said. "And for the health of our sport and the benefit of our sport, in my opinion, it is mandatory that we fix it."
Nadal joins Djokovic and Andy Murray calling for the unification of the 18-team Davis Cup with the 24-team ATP Cup, which staged group play in Brisbane, Perthy and Sydney.
Player Council president Djokovic bluntly said last fall tennis must combine the two events into one mega-event or run the risk of running one of the Cup competitions into extinction.
"I don't think they can both coexist six weeks apart for many, many years," Djokovic said. "Formats are very, very similar if not the same. Of course Davis Cup has the history behind it and tradition and of course the credibility and popularity of a hundred years.
"ATP Cup is a completely new event, but ATP Cup has a better week. It's the beginning of the season a few weeks before Australian Open starts. Most of the players are already on Australian soil so most of the top players are gonna play there."
Photo credit: ATP Cup Facebook