Roger Federer expressed mixed emotions over Davis Cup reforms.

While the 20-time Grand Slam champion favors innovation, he charged the International Tennis Federation "historically never involved the players" in the decision-making process and said the new Davis Cup format makes him "sad."

Watch: Federer Rallies Past Wawrinka

Federer and Stan Wawrinka led Switzerland to its first Davis Cup championship in history defeating host France in the 2014 final.

"Then for Davis Cup, I don't know how the votes work, to be honest," Federer said. "But clearly the ITF has never historically involved the players, but the federations, yeah, we're kind of there but we're actually not there.

"They decided to do that. I'm still a bit surprised. I didn't get involved because I didn't know the solution. It was definitely flawed in some ways, the Davis Cup, the way it was running the last few years, maybe the last decade or so, but last ten years. So for me, I don't know, I feel sad about it, you know, not to have the Davis Cup as it used to be. Will never be the same."

The International Tennis Federation approved a plan that will create an 18-team, year-end World Cup-style Davis Cup final.

Eighteen nations will compete in a week-long Davis Cup finale each November. The first edition of the new Davis Cup final format will be staged in either Madrid or Lille November 18-24th, 2019.

Skeptics say the new format diminishes the foundation of Davis Cup, diminishing the tradition of World Group home-and-away ties played over four weekends throughout the season. 

ITF president David Haggerty counters the reforms retain the home-and-away format for the February qualifying round and asserts the $3 billion, 25-year-year partnership with financial investment firm Kosmos to support the new format will not only mean more money for national tennis federations, but will also create a new player prize fund of $20 million.

The 37-year-old Federer says time will tell if the reforms are effective and referred to the ATP's failed 10-year, $1.2 billion partnership with sports marketing firm ISL as a cautionary tale.

"I just hope that every penny will be paid of that mass of money that has been paid for the next generation, because we have seen a similar situation way back when with the tour and it set us back in a big way," Federer said. "I don't want that to happen again. But, look, I'm all for innovation, and gotta give them a chance to some extent. It will be interesting to see how it's going to work. "

Photo credit: Davis Cup Facebook