Singapore - American legend Andre Agassi has said the International Premier Tennis League should take a lasting place in the sport despite a "shockingly uncomfortable" debut as he crashed to Mark Philippoussis on Tuesday.
The eight-time Grand Slam winner, 44, went down 6-3 in the Legends singles as hosts the Singapore Slammers lost 21-29 to Manila Mavericks on day one of the new team competition's second leg.
Agassi likened the IPTL's quickfire format, with one-set matches hurried along by a 20-second serve clock, to the pressure of facing his arch-rival, 14-time Slam champion Pete Sampras.
"I was shockingly uncomfortable today," Agassi told journalists at Singapore Indoor Stadium.
"It was just the pressure of it... So many times I felt that way against Pete because if you just lose concentration for a second on your serve, the set could be over with.
"And so every point was vital, that's part of the game. But with this format, it's that way with everybody, every match. It's a pretty difficult environment to play high-end tennis."
The new rules and scoring brought confusion, including in the final match when Serena Williams and Kirsten Flipkens dissolved into giggles as Williams realised she needed seven straight games to win the tie for Singapore.
When asked by the on-court interviewer afterwards how it felt to beat the world number one, Flipkens pointed to the scoreboard and said: "I didn't, she's still up 6-5."
Nenad Zimonjic was perplexed when he lost a game point by dropping his toss while trying for a second serve, and even the DJ had trouble keeping up when he played bursts of music while players were serving.
Agassi said teething problems were to be expected in a tournament which only started on Friday in Manila, and will move on to New Delhi and Dubai over the next 11 days.
"Those things are being worked out day-to-day but we're only a few days into it, everybody's getting a lot more comfortable," he said.
Agassi added: "You can't ever say that the pillars of the sport will morph into this, that's a stretch. We're a sport of great tradition.
"And nor do I think it necessarily should, but this needs to be a supplement to it, in my opinion... I just think there's too many wins not to find a place in the year for those that choose to do it."
Williams, returning to the arena where she won the WTA Finals in October, looked far from full fitness but said it was an "amazing" start to her pre-season preparations.
"I definitely would see myself playing this every year. It's a great environment to be involved in, and it's fun and it's a great way to get ready for the pre-season," she said.
In the earlier tie, Ana Ivanovic and Gael Monfils led the Indian Aces to a comprehensive 30-11 win over Marin Cilic's UAE Royals.