That contest ended in the Swiss star's favor, beating his old friend and rival 4-3 2-3 3-4 4-0 4-3 at Sydney's Qantas Credit Union Arena.
This new version of tennis, which marks some of the most significant rule changes
in the sport's history, consists of the best-of-three sets with quick changeovers and sudden-death playoffs to prevent tiebreaks from dragging on. The first player to four games wins the set.
"Playing Roger in this new format will be an exciting challenge for both of us and a lot of fun," said Hewitt ahead of the match.
The Australian roadshow will decamp to Melbourne next, with Spanish superstar Rafael Nadal taking on three opponents in separate matches Wednesday.
First he'll line up against former US Open finalist Mark Philippoussis before taking on current US Open junior champion Omar Jasika, finally playing a best-of-five match against compatriot Fernando Verdasco.
New game, new rules
Billed as tennis' answer to cricket's TV-friendly Twenty20, the two formats share more than just a catchy approach to branding.
Both take a fast-paced approach to sports that, for the uninitiated, could be considered soporific. Cricket traditionally takes five days to play a Test -- international -- match, and men's singles tennis can last for hours, or in some rare cases, days
Players will also have to hurry during end-changes, as there are no seating breaks and they get a scant 90 seconds to sit in between sets.
A couple of more fundamental rule changes, including the removal of the service let rule -- that requires a server to retake their service if the ball hits the net cord -- and the removal of the advantage point.
In FAST4, the receiving player gets to choose which side the serve -- for a sudden death "power" point -- is directed to at deuce.
Faster, glitzier tennis
FAST4 promises to provide some of the extravagance and glamor that, the majors aside, some evidently feel is missing from the sport.
Proponents hope that the truncated timeframe -- each set is supposed to last no more than 15 minutes, with games typically not lasting for much longer than an hour -- will allow for a greater number of people to find the time to play tennis.
"The new format is a game changer and is set to revolutionize the game of tennis, particularly at club and social levels," Tennis Australia' s chief executive officer Craig Tiley said.
"Time today is precious and this new fast format is perfect for any player who wants to fit their tennis matches into a busy lifestyle."
Tennis Australia high performance coach Craig Morris added: "Our long term objective in creating a product like FAST4 tennis is to attract more people to the sport, and get more people to play tennis.
"There's no plan to replace traditional tennis, this is a great complementary product that is entertaining for fans and fun to play."
It's not the only innovation that the sport is toying with.
The International Premier Tennis League
, "the first city-based professional league in the world, played across four countries," debuted in November in 2014.