Former Ventnor star Travis Head made a career-best 202 - then dedicated it to former South Australia teammate Phillip Hughes.

The left-hander struck a remarkable 202 from 120 balls in unlikely six-wicket victory against Western Australia on the opening day of Australia's domestic One-Day Cup.

A century had eluded Head in 41 matches for South Australia in all cricket.

But he now has the highest one-day score in the state's history, surpassing Matthew Elliott's 146 in 2007 - and it came in his first game as South Australia's one-day captain.

The 21-year-old, who is his state's youngest captain following a tumultuous period for his state that began with the death of teammate and friend Hughes, who briefly played for Hampshire in 2010.

Head, who had an aggregate of 200 runs from his nine previous one-day innings for South Australia, looked to the heavens and produced an emphatic fist pump after reaching his century.

"I guess there's that emotion," he told cricket.com.au. "I was looking up at Hughesy and I hadn't got one since [he passed] so it was a pretty big moment.

"I just wanted to start the tournament really well and hopefully he's looking down.

"I actually equalled his highest score in one-day cricket, but unfortunately he was not out so he'd be into me for that!"

Head, who made 969 run sat 64 in for Ventnor in the Southern Electric Premier League, struck 20 fours and 12 sixes as South Australia chased down the defending champions' 350-4 to win by six wickets with 21 balls to spare.

He shared a third-wicket stand of 278 from 194 balls with Callum Ferguson (112no) - the highest-ever partnership for South Australia in the 50-over format.

Head, who has been backed for a full Australia call-up by Ricky Ponting and Darren Lehmann added: "Anyone would want to push with so many opportunities.

"Boof (Lehmann) had some kind words for me, but it's just about getting runs and that's easier to say now that I've got 200.

"I've just got to go through my routine and keep trying to bat the way I'm batting. I was really clear in my plans, which is key for me. Hopefully it's the start of a big summer."