A maiden World Cup century from Sanath Jayasuriya inspired Sri Lanka to a comfortable 47 run victory in their crucial Pool B World Cup clash against New Zealand on Monday.

Jayasuriya smashed a characteristically belligerent 120 from 125 balls and veteran Hashan Tillakaratne compiled a workmanlike unbeaten 81 as Sri Lanka scored a very competitive 272.

New Zealand's run chase was ended almost as soon as it had begun after a frenetic start that saw them crumple to 15 for three in the sixth over.

A spirited 78-run partnership between Scott Styris and all-rounder Chris Cairns (32) briefly threatened to breathe life into their run chase before the loss of further wickets.

Styris carried on to score a maiden one-day century - a fine, hard-working innings that included five sixes and three fours - but he steadily ran out of partners and time

The Black Caps, who look set to lose valuable points after refusing to travel to Kenya, now face an uphill struggle if they are going to qualify for the Super Sixes stage of the competition.

For Sri Lanka, it was a polished performance that gave credence to their recent claims that they are finally adjusting to unfamiliar conditions and peaking at the right time.

But the key to their recent revival has undoubtedly been the purple patch of form currently being enjoyed by Jayasuriya, who has already scored three hundreds and a 99 this year.

Jayasuriya also enjoyed some good fortune, surviving a very good appeal for a catch at the wicket when he had scored just 14, a decision that left the New Zealanders understandably aggrieved.

The 33-year-old didn't look back after the let-off, kick-starting the innings after the early loss of Marvan Atapattu (6) with a stream of withering square drives and cuts.

He raced to a 45-ball fifty with a boundary and then moved into cruise control after the initiative had been won, progressing smoothly to his 16th one-day hundred.

Jayasuriya added 170 with Tillakaratne, a record World Cup partnership for the second wicket for the Sri Lankans, and on 193 for one in the 35th over a 300-plus total appeared possible.

However, the introduction of gentle medium pacer Nathan Astle slowed Sri Lanka's momentum as he picked up the wickets of Jayasuriya, Aravinda de Silva (12) and Kumar Sangakara (13).

Tillakaratne, hampered by leg cramps during the latter part of his innings, bound the innings together as the middle order failed to provide the expected fireworks in the slog overs.

Nevertheless, the final total proved ample on a slow pitch that was always likely to provide some encouragement for Sri Lanka's quartet of spinners.

Earlier, New Zealand appeared to have misread the pitch, gambling on a four-pronged pace attack at the expense of their world-class left-arm spinner Daniel Vettori.

That left the Black Caps needing to start well against the harder ball if they were to have a chance of challenging Sri Lanka's total.

However, they started in disastrous fashion as Astle (0), who could have been run out without facing and then trapped lbw first ball, was run out by a direct hit from Chaminda Vaas in the first over after attempting a suicidal run.

Stephen Fleming (1) and Craig McMillan (3) then edged catches to wicket-keeper Kumar Sangakkara off the bowling of Pulasthi Gunaratne.

Cairns and Styris then started the repair work in diligent fashion, rotating the strike well and scoring freely as Jayasuriya refused to go for the killer blow.

But veteran de Silva made up for his failure with the bat by deceiving Cairns with his part-time off-breaks and clutching onto a simple return catch.

Lou Vincent (3) was caught in the covers in the next to leave New Zealand back on the rack at 94 for five. Chris Harris (13) added 56 valuable runs with Styris before being deceived by Muttiah Muralitharan.

Thereafter, Jacob Oram (12) and Styris struggled to keep pace with the required run rate and New Zealand were left searching something spectacular, needing 97 runs from the last ten overs.

Oram eventually swung a catch into the deep and Arnold, Sri Lanka's fourth spinner, snared Andre Adams and Darryl Tuffey.

Styris threw caution to the wind, smashing three sixes before holing out in the deep, his disappointment softened by the fact he had posted the highest individual score at the venue and the second highest ever by a Kiwi.