Serena Williams saved five match points in a monster final game to exit the US Open third round to Australian Ajla Tomjlanovic on Friday – her earliest loss at the event since her 1998 debut and the end of her tennis career.

The 40-year-old who will now announce her retirement in the coming days, received a cheering send-off ceremony laid on by the tournament.

“I tried but she played a little bit better,” the 23-time Grand Slam winner said before starting to choke up in front of an adoring full house of 23,000 in the Ashe stadium.

Serena Williams waves to the capacity crowd after losing her third round match at the US Open, ending an illustrious career spanning three decades and winning 23 Grand Slam titles. Photo: Roger Parker International Sports Fotos Ltd

She thanked her parents and elder sister Venus: “There wouldn’t be a Serena if there was not Venus, thank you Venus.

“She’s the only reason Serena Williams existed.

“It’s been a fun ride,” she told the crowd. “I’ve been on the most incredible journey of my life.

Tomljanovic held her nerve through the tense final game as Williams threatened in the tight final game.

But the Australian admitted: “I thought she would beat me” in the three-hours epic.

“The pressure was not on me but on her. But she is Serena and she is always in a position to win – even from 5-1 down.

“I didn’t think even until the last point that I could win.”

Tomljanovic called Williams “the greatest of all time – period.”

The Australian said she lost the second set “by not doing much wrong.

“But I couldn’t dwell on it, I had to take one point at a time, literally.”

Serena Williams takes a bow after losing to Ajla Tomjlanovic on Friday evening. Photo: Roger Parker International Sports Fotos Ltd

Tomljanovic ended with 32 winners and 30 unforced errors while the Williams numbers were 14 and 25; Williams was broken eight times.

“I never thought that I’d have a chance to play her in her last match,” the winner said of Williams. “This is a surreal moment for me.

“I will miss seeing Serena on the court – it won’t be the same.”

Tomljanovic dropped serve to love to trail 3-5, opening the door for Williams in the first set. But the chance went begging as the Australian broke straight back to pull to 4-5.

Tomljanovic started swinging freely, holding to level at 5-all and taking a 6-5 lead on the fifth break of the set.

She lifted the set after 50 minutes with a cross-court winner on her third set point with Williams committing 16 of her unforced errors.

In the second set, the American crowd darling raced off to 4-0 in the second set but stalled.

After getting to 5-2, Williams had to defend against a fightback from her Aussie opponent, who raised the stakes as she climbed to 3-5 after saving four set points.

Williams double-faulted away her service game as her lead narrowed, 5-4; Tomljanovic made it five apiece moments later and sent the set into a tiebreaker two games later.

The Australian successfully played catch-up in the decider, coming from 4-1 down but sent a forehand wide down the line as Williams levelled the sets on her fifth chance.

Serena Williams’ career comes to an end after her third round loss in New York. Photo: Roger Parker International Sports Fotos Ltd

In the third set, Tomljanovic neutralised an early break of serve for 2-1 and broke again for 3-1 thanks in part to a pair of Williams double-faults.

The Australian held for 4-1 as hopes for Williams began to fade despite massive support form the majority of the crowd.

Williams scooped a return long over the baseline to lose serve as her opponent rolled into a winning position at 5-1.