Australia notched a comfortable three-wicket victory over England in the opening match of the tri-nation One-day cricket series at Sydney on Friday. Continuing his blazing form, David Warner struck a scintillating hundred to guide the hosts to victory.Batting first, England were subjected a top-order collapse despite skipper Eoin Morgan's brilliant counter-attacking 121 which took the team total to 234 in 47.5 overs. None of the other England players even crossed 30-run mark. In reply, Warner's 115-ball-127 laid the foundation as Australia scored the required runs in 39.5 overs . Having achieved the target within 40 overs, Australia earned a precious bonus point. India will take on hosts Australia in their first match of the tri-series on Sunday in Melbourne . Ahead of this opening clash, MS Dhoni is under the spotlight as he returned to the arena where he announced a shock Test retirement last month. He has remained with the squad here, travelling and even showing up in the Sydney nets but he has not spoken a word about his surprising decision. The tri-series, is seen as a final warm-up for all the three teams ahead of the World Cup, to be co-hosted by Australia and New Zealand in less than a month's time.