Mahela Jayawardene and Tillakaratne Dilshan took full toll of a wayward Australia as Sri Lanka forced a third triangular series final in Adelaide. Chasing 272, the visitors galloped to the target with 5.4 overs to spare, benefiting greatly from a rollicking start when the first three overs reaped 30 runs.

Dilshan alternated between the brazen and the cheeky, crashing 10 fours and also being struck on the helmet when he attempted his patented Dil-scoop. The captain Jayawardene was more cultured, but outpaced his partner in a princely innings that would have ended in the second over if not for a Clint McKay no-ball.

Such indiscipline summed up Australia's predicament, having struck a horrid patch of form in the field midway through the first final in Brisbane and then being unable to rise above it in Adelaide. The captain Michael Clarke is also in the unenviable position of carrying a left hamstring problem perilously close to the start of the West Indies tour, due to begin almost immediately after the third final.

Clarke had done his best to give his side a decent total. His 117 in Australia's 6 for 271 was the fastest of his limited-overs career and the second of his ODI captaincy. David Warner was more circumspect, but his chanceless 100 demonstrated a range of concentration and focus reserved for the best of batsmen. Famed as a boundary hitter, Warner reached the rope only four times in his innings and cleared it only once, but the value of his effort was reflected in a final total far greater than seemed possible at the innings' midpoint.

Matthew Wade departed early to the spin of Dilshan, who opened the bowling and completed a tidy 10 overs, before Shane Watson played a chancy innings in which he was grassed twice. Each dropped catch fell off the bowling of Farveez Maharoof, who ultimately ran out Australia's vice-captain with a direct hit in his follow through. Lasith Malinga was the tightest of Sri Lanka's bowlers and deserved his three wickets.

Two more catches would go down off Clarke's bat later in the innings, while Jayawardene raged against a delayed no-ball call at the height of his opposite number's innings. Debating the point angrily with both umpires after Maharoof had strayed above waist height with a full toss, Jayawardene lost his cool. His fury would be far more controlled when the reply began.

A second-over edge behind by Jayawardene was cancelled out by McKay's overstep, typical of the abject way in which Australia's bowlers began their defence of a less than watertight total. Brett Lee gave up three wides on the way to conceding 12 from the opening over, and James Pattinson's first two overs were taken for 22 despite an abundance of away swing.

No fewer than 11 of the first 30 runs were handed to Sri Lanka via the extras column, as Australia's bowlers maintained the poorly form they had demonstrated in the latter overs in Brisbane. Clarke had taken the field despite his injury, but his presence did not make much of a difference.

Jayawardene and Dilshan did not get too frantic after the start they were given, and slipped into comfortable gears that involved regular singles and the odd boundary whenever the bowlers strayed in search of a first wicket. Australia's mid-innings options were milked for regular runs, Xavier Doherty's first five costing 37.

Dilshan was first to pass 50, and Jayawardene soon followed. Australia's frustration grew when Asad Rauf refused a concerted appeal for caught behind from Dilshan on 77, as replays revealed a substantial edge that Wade gathered while keeping up to Watson.

Jayawardene's sparkling stay was ended by a hint of Pattinson reverse swing and a clear lbw, but Dilshan went on to his second century of the tournament before Dinesh Chandimal and Kumar Sangakkara guided the visitors home.

Clarke had little hesitation batting upon winning the toss, but the early overs were slow going. Jayawardene's imaginative use of Dilshan added to the openers' uncertainty, and Wade's impatience proved terminal when he swung at a ball not quite short enough for the stroke and was bowled.

Watson's innings was halting, and he was dropped by Dilshan in the fielding circle then by Rangana Herath on the long-off boundary - the latter unable to complete an equivalent of his spectacular outfield take in the first final. However Maharoof was not discouraged by the missed chances, and when Watson was 15 he gathered and swivelled from Warner's offside bunt to throw down the stumps and find a diving Watson comfortably short. Clarke helped to build some greater momentum in the company of Warner, who was less conspicuous than he had been at the Gabba.

The pair accumulated steadily, adding a little more impetus with the batting Powerplay, and continuing to benefit from profligate fielding from the tourists. Clarke was turfed on 71 and 77, the second chance falling to Malinga, who managed only to palm the chance over the rope for six.

It set the scene for an explosive over, in which Clarke took Maharoof for six, four, six, four - the last a high full toss swung behind square leg. Initially the umpires did not call it a no-ball, but on reflection Bruce Oxenford raised his arm to hand Australia an extra run and another delivery. Jayawardene was incensed by the delayed call, arguing at length with both officials in a manner that suggested more of the incident would be heard later.

Clarke had blazed past Warner despite the opener having a 23-run start, and he was first to reach his century with a flick through square leg. Though he had made plenty of useful contributions in the interim, it was Clarke's first ODI century since his first innings as the fully-fledged captain, against Bangladesh in Dhaka in April 2011.

Warner's hundred arrived in the next over, an effort of composure and also courage after his groin complaint in Brisbane. He skied a catch without adding another run, leaving an increasingly restricted Clarke to guide the hosts to a total rather less substantial than was ultimately needed.