The world number one last played at the event, often referred to as the fifth grand slam, in 2001, having boycotted the event after accusations that her family were racially abused while she faced Kim Clijsters in the tournament final.
The reception Williams received when she stepped out on court on Friday night can be described as anything but hostile. Williams was moved to tears by the crowd reaction when her name was announced prior to the match, and continued to fight a losing battle to hold back tears while she unpacked her racquets.
The emotion continued on court, with Williams often crying out and pumping her fists in celebration.
Her tennis was not quite as impressive as she would have like though, with both players looking tight in a match that served up a fair few errors.
The pair traded breaks in the first set with alarming regularity, with Williams broken twice and Niculescu three times, handing the American the set.
The quality of play didn't improve much in the second set, and Williams wasted match points at 5-4 up before finally seeing out the contest 7-5.