SINGAPORE — Serena Williams returned to the scene of her WTA Finals win but could not prevent her Singapore Slammers team slumping to a fourth straight defeat in the inaugural International Premier Tennis League (IPTL) Tuesday. The world No. 1 is the highest-profile player participating in the four-city mixed team event at Singapore's Indoor Stadium this week but it was the unbeaten Delhi-based Indian Aces who continued to dominate the early proceedings. The Aces were on court first as a sparse crowd witnessed the form side of the tournament ease to a 30-11 victory over the UAE Royals in the five one-set format tie that is decided on games won rather than overall set victories. Playing in front of a packed arena in the night session, Williams won her match against Belgian Kirsten Flipkens but lost the mixed doubles, partnering Australia's Nick Kyrgios, as her team fell 29-21 to the Manila Mavericks. The tournament kicked off in Manila Friday and will proceed to Delhi before concluding in Dubai on Dec. 13, the event mirroring its India-based cricket counterpart by adding bright lights, glitz, glamor and audience participation to a fast-paced format. Additional touches include a 20-second serve clock, a ‘Happiness Power Point' joker that scores double and can be played once per set, no advantages, no lets, coaching timeouts and a five-minute shootout if a match is tied at 5-5. American legend Andre Agassi said the IPTL should take a lasting place in the sport despite a “shockingly uncomfortable” debut as he crashed to Mark Philippoussis Tuesday. The eight-time Grand Slam winner, 44, went down 6-3 in the Legends singles as host the Singapore Slammers lost 21-29 to Manila Mavericks on day one of the new team competition's second leg. The new rules and scoring brought confusion, including in the final match when Serena and Flipkens dissolved into giggles as Williams realized 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.” After four rounds of matches the Indian Aces lead on 16 points, ahead of the Manila Mavericks and UAE Royals on 11 points with Singapore propping up the table on six points. — Agencies