Dilshan scored 92 runs in Sri Lanka's first innings and scored quickfire 123 runs in the second to take Sri Lanka to an imposing target of 413.
"When you look at how well Dilshan played and how poorly we bowled to him, it was probably the defining moment of the game," Stuff.co.nz quoted Vettori, as saying.
"There were a couple of opportunities there to put pressure on them, but everything we did, he took it away from us. He played exceptionally well, he played very aggressive innings, and when you've got a player like that, it makes it very tough to captain," he added.
Vettori said that he wanted to take the game to the wire, however, failed to do so, as multiple players being ill in the team meant that they were bowled out for a meager 210 runs.
"I really hoped we'd take it down to the wire. I hoped that we could bat for long periods of time, but in some ways a few illnesses counted against us and the application wasn't quite there," Vettori said.
He further said that one of the most disappointing things in the Test was to lose as many wickets to the seamers as they did.
"Obviously Murali's a difficult customer to come up against but the way Thushara bowled was probably where we let ourselves down," Vettori said.