"The coach and captain said we should go and play positive."
As for his own performance, in his fourth ODI, "it came on to the bat really nicely, it was a good track I guess luck was on my side today."
New Zealand now have to pick themselves back up, after taking a resounding 2-0 lead in Christchurch, only to get a thorough beating.
"He's a world class player," New Zealand allrounder Mitchell Santner said of the 29-year-old Dilshan.
"We knew he'd had a couple of failures and was obviously due some runs and really cashed in and played really well, to be fair."
Gunathilaka played "a serious knock, really put us on the back foot early doors and it was quite hard to come back from that".
Santner's figures, none for 59 off 10 overs, were no worse than most of his bowling team mates but he'll benefit from the experience.
"Every time you're out there it's an experience.
"Obviously I didn't bowl as well as I would have liked but you take the learnings for the next game and hopefully build on that."
New Zealand are having a day off from the nets tomorrow and they figure it's only small aspects they need to sharpen on. However they now sense Sri Lanka are right back series.
Dilshan, Lahiru Thirimanne and Dinesh Chandimal are key batsmen. All made runs today, and Chandimal carried decent form in from the test series.
Add in the rising talent of Gunathilaka, plus the fact captain Angelo Mathews is overdue runs and New Zealand will recognize this series just got a lot tougher.
New Zealand seamer Tim Southee has been ruled out for the rest of the series after injuring his left foot in the loss to Sri Lanka.
Canterbury's Matt Henry returns to the team after taking eight wickets in the first two one-dayers.
Southee's injury will be further assessed on Friday.