German tennis stalwart Steffi Graf has paid a glowing tribute to Serena Williams for the way she has continued to fight for titles even into her late thirties.

Weighing in on the ‘GOAT’ debate in women’s tennis at a virtual session of the Hindustan Times Leadership Summit, the 22-time Grand Slam winner put the American ahead of herself in the order of best ever.

Serena Williams’ accomplishments incredible, says Steffi Graf

Graf appeared for the session along with her husband, six-time Grand Slam winner Andre Agassi.

She said Serena’s accomplishments in tennis are nothing short of remarkable.

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The American broke Graf’s record for most Major titles in women’s tennis with her 23rd Grand Slam title at the Australian Open in 2017.

Giving her assessment of where she sees her onetime rival in the ‘GOAT’ race, Graf said, “Serena’s accomplishments have been incredible.”

Graf marvels at Serena’s determination to defy age

Drawing her own career into the discourse, Graf, now a mother of two, said she was mentally prepared to step away from tennis before she hit her thirties and said it’s commendable how Serena has carried on, defying skeptics, even in her late thirties.

Now 39, Serena has no plans to set her racquet down for good. She follows a fitness routine that would put even a teenaged rival to shame.

Graf said she marvels at the American’s ‘mental toughness’ and motivation to compete even at 39.

“I was ready to retire at 29-30 but seeing her mental toughness…how she’s out there and determined, it’s amazing,” Graf said.

Thankful to be there, says Graf on being in ‘GOAT’ race with Serena

She said she isn’t too bothered where she ends up in the race for the greatest in the women’s game and is happy to even be considered in the ‘GOAT’ debate.

“In terms of greatest of all, to be mentioned in that and being recognized for it, I feel thankful. I don’t lose any sleep about it,” said the German legend.

Graf racked up four Australian Open titles, six French Open titles, seven Wimbledon crowns and five US Open trophies over the course of a glorious 17-year career.

The German featured in just two matches against Serena – in Sydney and the Indian Wells – in 1999.

Their head-to-head record stands at 1-1.