Chasing a victroy target of 136 runs, New Zealand needed 10 runs off the last over from express fast Lasith Malinga.
Nathan (16 off 6 balls), younger brother of Brendon, struck a four moving across the off stump and piercing the gap in the fine leg to bring the equation down to four off three balls. New Zealand skipper Daniel Vettori (17) was run out while going for a second run in the next ball. Nathan then struck a powerful blow over long-off for a six to spark celebration in New Zealand camp.
It was Jacob Oram who pulled his team back in contention in an engrossing battle after Jesse Ryder (42 off 27 balls) and Martin Guptill (19) laid the foundation for the chase with a 62-run stand following the first over dismissal of Brendon.
With 38 runs required off 20 balls, big hitting Oram (15) hit two sixes off Mendis in the 17th over to revive Kiwi hopes.
But Chanaka Welegedera bowled a superb 19th over, removing Oram in the first ball and then Hopkins was run out in the next. Vettori, who anchored the New Zealand innings in the later half, struck a four while Nathan stole three runs taking advantage of a missed run out chance to give themselves a real chance of finishing the match in the last over.
Earlier, Ryder and Guptill batted sensibly in a slow and spinning track to set the match for the Kiwis.
Ryder mixed caution with agression and struck three fours and two sixes in his 27-ball innings. But the introduction of two old war horses Muttiah Muralitharan (2-25) and Sanath Jayasuriya (1-17) slowed down the runs.
Ryder after hitting a six off Muraliatharan was clean bowled in the next ball while Jayasuriya got rid of Guptil in the next over (10th) with a yorker.
The spinners made it difficult for the Kiwi batsmen to score runs even as Vettori held the innings from one end. Scot Styris contributed 17 before Oram lead the fightback.
Sri Lanka after electing to bat first relied on Mahela Jayawardene brilliance to set up a challenging total.
Jayawardene smashed 81 off 51 balls as Sri Lanka posted 135 for six.
Jayawardene guided Sri Lanka through a difficult phase after the islanders made a slow start before recovering in the final overs.
Dinesh Chandimal was the second best contributor with 29 runs off 23 balls with the help of one four and one six.
New Zealand bowlers made good use of the slow track, taking the pace off the ball and not allowing dangerous Sri Lankan opener Tillekaratne Dilshan to get off to a good start.
Dilshan made just 3 off 19 balls before Jacob Oram rattled his stumps.
Sri Lanka found it difficult to score in the first 10 overs that fetched them only 54 runs. Jayawardene played with patience and waited for the bad balls to score.
He struck eight fours and two sixes before Tim Southee got his wicket in the 19th over.
SCOREBOARD
Sri Lanka:
Mahela Jayawardene c N McCullum b Southee 81
Tillakaratne Dilshan b Oram 3
Kumar Sangakkara b Styris 4
Dinesh Chandimal c Taylor b N McCullum 29
Chamara Kapugedera c NL McCullum b Bond 11
Angelo Mathews c NL McCullum b Bond 3
Sanath Jayasuriya not out 0
Extras (lb 3, w 1) 4
Total (for six wickets in 20 overs) 135
Fall of wickets 1-35 (Dilshan, 5.4 ov), 2-44 (Sangakkara, 8.2 ov), 3-103 (Chandimal, 15.4 ov), 4-124 (Jayawardene, 18.1 ov), 5-135 (Kapugedera, 19.4 ov), 6-135 (Mathews, 19.6 ov)
Bowling:
Nathan McCullum 3 0 17 1
Shane Bond 4 0 35 2
Tim Southee 4 0 21 1
Jacob Oram 3 0 23 1
Daniel Vettori 4 0 23 0
Scott Styris 2 0 13 1
New Zealand:
Brendon McCullum c Malinga b Mathews 0
Jesse Ryder b Muralitharan 42
Martin Guptill b Jayasuriya 19
Ross Taylor c Mathews b Muralitharan 9
Scott Styris b Mendis 17
Daniel Vettori run out (sub S Randiv/Malinga) 17
Jacob Oram b Welegedara 15
G Hopkins run out (Dilshan/Sangakkara) 1
Nathan McCullum not out 16 6
Tim Southee not out 0
Extras (b 2, w 1) 3
Total (for eight wickets in 19.5 overs) 139
Fall of wickets 1-0 (BB McCullum, 0.4 overs), 2-62 (Ryder, 8.3), 3-66 (Guptill, 9.5), 4-86 (Taylor, 14.2), 5-96 (Styris, 16.2), 6-116 (Oram, 18.1), 7-117 (Hopkins, 18.2), 8-133 (Vettori, 19.4)
Bowling:
Angelo Mathews 2 1 7 1
Chanaka Welegedara 2 0 21 1
Ajantha Mendis 4 0 34 1
Lasith Malinga 3.5 0 33 0
Muttiah Muralitharan 4 0 25 2
Sanath Jayasuriya 4 0 17 1
