Former tennis star Sam Groth is switching implements and having a crack at the Port Phillip Open Amateur which begins at Kingston Heath on Thursday.

The 72-hole stroke event, one of the most prestigious in Australian amateur golf, also serves as the qualifying event for the Victorian Amateur at Metropolitan next week.

To reach that field, the 33-year-old Groth needs to make the top eight at the Port Phillip Amateur, which concludes at his home club, Commonwealth, on Saturday.

Groth is no slouch on the golf course; he plays off a 1.3 handicap at Commonwealth and is renowned for his monumentally-long hitting. He has been a fixture at pro-ams in recent years having retired from professional tennis in 2018 with the fastest-ever service of 263 km/h.

"Once I stopped playing tennis, golf filled that competitive void," Groth told Golf Australia today. "I've gone from a handicap of about 20 to ... a couple of weeks ago I was off zero-point-zero, so I've blown out a little bit! My wife's pregnant with twins so I haven't been out as much as I'd like! "I love it. I'm part of the pennant squad at Commonwealth. Being a competitive person and coming from a one-on-one sport, when the Port Phillip came up and it fitted into my calendar why wouldn't I play?"

He is far from the first to have come from a high level at another sport. Former St Kilda and Essendon AFL star Brendon Goddard played in the Port Phillip Amateur last year.

Groth has always played golf, having grown up in Corowa and being a close friend of touring pro Marcus Fraser. His father, Phillip, was a two-marker.

But he knows this is another level. "There's a lack of expectation. I'd like to do well. My competitive side takes over and I don't want to make up the numbers. Coming from my background, I'm not going to shy away from competition."

Groth will need to be at his very best this week. Recent border openings have given this week’s event the strongest field at any amateur tournament in 2020, with waves of the country’s top players coming in from interstate.

There are 151 men playing and 24 women in the field.

VIS player Andre Lautee, winner of the past two Victorian Amateur championships, is in the men’s field, along with the likes of multiple state amateur champion Louis Dobbelaar of Queensland, and New South Wales players Harry Bolton and Harrison Crowe.

Mt Lawley’s Kirsten Rudgeley heads the women’s field, but she will have strong competition from the likes of Youth Olympics gold medallist and last year’s Port Phillip runner-up Grace Kim (NSW), and Victoria’s Stephanie Bunque.

Rudgeley, who plays off a plus 6.1 handicap, is the reigning WA Amateur champion and last year made history by becoming the first female to make the cut at the WA Open.

Port Phillip Open Amateur field, tee times, information