Serena Williams is not ready to say goodbye just yet. Nor, clearly, are her fans.

 In her first match at what is expected to be the last US Open — and last tournament — of her remarkable playing career, Williams overcame a shaky start to overwhelm Danka Kovinić 6-3, 6-3 on Monday night in a packed Arthur Ashe Stadium with an atmosphere more akin to a festival than a farewell.

Williams still didn't definitively say she was retiring during a ceremony after her first-round victory over Kovinić. But the 23-time Grand Slam singles champion made it clear she is ready for different things, saying "there's other chapters in life."

She promised that whatever she does after tennis, she will still be intense, like she was as a player, saying her next chapter will be "like Serena 2.0."

The ceremony, which included her husband and daughter coming onto the court as well as Billie Jean King, included a tribute narrated by Oprah Winfrey, titled Dear Serena. It ended by saying: "Just know whatever you do next, we'll be watching. With love, all of us."

Early, Williams was not at her best. Maybe it was the significance of the moment. There were double faults, other missed strokes, missed opportunities. She went up 2-0, but then quickly trailed 3-2.

Then, suddenly, Williams, less than a month from turning 41, looked a lot more like someone with six championships at Flushing Meadows and 23 Grand Slam titles in all — numbers never exceeded by anyone in the professional era of tennis, which began in 1968.

She rolled through the end of that opening set, capping it with a service winner she reacted to with clenched fists and her trademark cry of "come on!".

The more than 23,000 in the stands (thousands of others watched on a video screen outside Ashe) rose for a raucous standing ovation — and did so again when the 1-hour, 40-minute contest was over, celebrating as if another trophy had been earned.