Organisers said in October that the Melbourne Park major was switching to a 15-day tournament and would start on a Sunday for the first time in its 119-year history.
The French Open made a similar move in 2006 while the other Grand Slams at Flushing Meadows and Wimbledon remain 14-day tournaments.
While the Roland Garros decision was aimed at giving the tournament more exposure, particularly on TV, Australian Open organisers said their move was made with player welfare in mind, with data showing matches now lasted longer.
The extra day on the schedule allows Rod Laver Arena and Margaret Court Arena to feature two matches instead of three in the day session, meaning there will be no spillover to the evening session.
Reigning champion Djokovic, who founded the Professional Tennis Players Association, was keen to see if the changes would help.
"I guess that's one of the motives behind starting on Sunday," he told reporters on Saturday.
"Obviously there are other Slams that start on Sunday. Roland Garros starts on Sunday, as well.
"That's going to help, I'm sure, get some matches out of the way, reorganise the schedule better in the opening week which is always very busy with a lot of matches on the schedule that need to be finished in a proper time.
"Let's see if that works out."
Five-time finalist Andy Murray has also welcomed the change. The Scot was involved in one of the latest ever finishes at the Grand Slam when his five-setter against Thanasi Kokkinakis went on until 4:05 a.m. the next morning.
"That will reduce the possibility for late finishes on Rod Laver Arena," Murray said on Friday of the schedule change.
"Because it's unlikely you're going to have issues with the day session running into the night, then having that gap where they have to clear out the stadium and get the night session fans in."
Women's world number one Iga Swiatek said that the switch to a 15-day tournament made sense.
"I think schedule-wise it's going to be a little bit easier for the tournament to finish matches earlier," Swiatek added.
"At the end it's just the first day, then the tournament goes back to normal after these Sunday matches. People have two days off then it goes back to normal. It doesn't really matter."
The additional day also makes financial sense for organisers, who are looking to refill their coffers after reporting a net loss of more than A$100 million ($66.85 million) in 2020-21 amid the COVID pandemic.
Seven-times major champion McEnroe is not a fan of the change.
"First of all, it's a money grab as far as I'm concerned," the American said in a conference call earlier this week.
"They just found another way to make some money. I don't agree with it.
"The players, if they accept it and are getting something from it, like some money for their pensions or retirement for some players that don't have insurance, I would say that's a good thing that they have added an extra day.
"I don't think that's happened, just like it didn't happen at the French Open. I completely disagree with it."