Bob Hawke sings Waltzing Matilda at Mother's Day polo match

ausWith just one song, Bob Hawke has cemented his status as the most patriotic man in Australia – again.

The title won three years ago, when he was filmed skolling a beer at the cricket, was reinforced on Saturday afternoon in Sydney’s west when he took to the stage to deliver a rousing rendition of Waltzing Matilda, just one year on after he surprised organisers and guests at the same event the previous year.

Hawke was a guest at Richmond’s Kurri Burri polo club for the Mother’s Day Classic when he learned it was the birthday of someone in the crowd.

So he did the obvious thing – climbed on stage, complete with his walking stick, to deliver bush ballad and unofficial national anthem Waltzing Matilda.

The result adds to what’s surely a growing file: ‘Bob Hawke being patriotic on camera’.

As Hawke injected his performance with personality, waving his walking stick around to conduct the crowd, he was backed by musicians Thomas Busby and Jeremy Marou (from Rockhampton band Busby Marou), who happily sang along, clearly at peace with being outshone by the 85-year-old former Prime Minister.

In a post to the band’s Instagram, singer Busby praised Hawke’s performance, calling Hawke their “best support act yet”.

The crowd took warmly to the impromptu performance, clapping and cheering along. Witness Brony Popp described the performance, at around 3pm, as “amazing”.

“It was so hilarious and everybody was singing along,” she told Fairfax Media.

“It was unannounced, I didn’t know it was going to happen. We just went to the event today and they said Bob Hawke’s going to sing Happy Birthday to, I think, one of the daughters of somebody from the club. Then he ended up singing Waltzing Matilda, so it was very cool.”

With his encore over, Hawke stepped from the stage and joined wife Blanche d’Alpuget to take photos with waiting fans, before the pair sat down in time for the next game of polo.

It was her first time at polo match, but Ms Popp has been left with a lasting memory, “It was such a great day,” she said.

Hawke, who was Prime Minister from 1983 to 1991, famously set a world record for downing a yard glass of beer when he was a student at the University of Oxford in the 1950s.