I do not know why sides who loses the last match when the series is already won say, that this last match wasn't important when they are being paid for every match to perform to their full potential and win for their country.
I think Sri Lanka is focusing only on test matches, because they always made a good performance in test matches since the previous year started, beaten to Pakistan and New Zealand very well that was a really unexpected results but now they are just trying to maintain good results in all formats but somehow cannot achieve it.
However, already Sri Lanka lost the series but they won the last match. At least they have something to cheer about at the end of the series but that changes nothing about the Sri Lanka's bad performance in the whole series.
The result of last ODI showed that Sri Lanka is not an ordinary side and must not be taken as for granted. Also if Sri Lankans have the potential which they displayed today then why not they showed it in first two games, why they waited for 2 consecutive loss to regain the form. Sri Lankans were in complete command of the game today, first in batting they scored 290 runs and then in bowling they didn't allowed New Zealanders to score runs. Chapman was the only New Zealanders who score runs today but his knock was not enough because of no support from other end.
I never thought that Sri Lanka would perform so well in the last match after losing two matches in this series. I am sure that the New Zealand fans are extremely disappointed with the great performance of the Sri Lankan players in the last match. The New Zealand fans are very angry with the unexpected performance of the New Zealand players in this match. I think that the New Zealand team did not play this last match seriously after winning the previous two matches. The New Zealand team was extremely embarrassed in this match because of the unimportant performance of the New Zealand players. However, it must be admitted that in this last match, the Sri Lankan team has won the hearts of cricket lovers by showing great surprises in batting and bowling.