John Hastings claimed six wickets before Aaron Finch and George Bailey's attacking half-centuries powered Australia to a series clinching six-wicket win over Sri Lanka in the fourth one-day international in Dambulla on Wednesday.

Australia rode on Finch's 19-ball 55 and an unbeaten 90 from Bailey to chase down 213 in 31 overs and take an unassailable 3-1 lead in the five-match series.

Finch, who equalled the record for the fastest fifty -- in 18 balls -- by an Australian, struck eight fours and three sixes as he carted the Sri Lankan spinners to all parts of the ground.

Earlier Hastings' career-best bowling figures of 6-45 helped bowl out Sri Lanka for 212 after electing to bat first despite Dhananjaya de Silva's fighting 76.

The victory comes as a welcome relief for the visiting side after they suffered their first series whitewash against Sri Lanka in the three Test matches.

The fifth and final match of the series is scheduled on September 4 in Pallekele.

SCORES IN BRIEF

SRI LANKA:  212 all out in 50 overs (De Silva 76, Mathews 40, Pathirana 24; Hastings 6-45)

AUSTRALIA: 217 for 4 in 31 overs (Finch 55, Bailey 90 not out, Head 40; Pathirana 3-37)

Result: Australia won by 6 wickets and led 5-match seies 3-1.

Player-of-the-match: John Hastings.