The Blackcaps have had to settle for a draw in their three-day warm-up match against Sri Lanka Cricket President's XI in Colombo after rain washed out the final day.
Overall, only one day of play was completed, as day two was also washed out due to rain.
The match was their first outing since last month's Cricket World Cup final, and their only warm-up match ahead of a two test series against Sri Lanka, which starts in Galle on Wednesday.
The locals ended the first day on 323/6, with Blackcaps spinner Ajaz Patel taking 5/40 with the ball.
"We bowled 60 overs, and that was it," said Williamson. "It was nice to get outside, but not much else to report.
"We've just been trying to get in as much practice in. Mother Nature is not playing its part at the moment, so we'll keep training indoors before heading to Galle tomorrow."
One of the highlights from the match though was on day one when Williamson ran over to eat some cake with Sri Lankan fans to celebrate his birthday.
"There were lots of surprises and lots of cake," Williamson added. "The fans were chanting 'happy birthday' so I ran over and said 'hello'.
"I could see a guy had a cake so I thought I'd run over and share it with him. It was all good fun, so I took a chance to hang out with the fans."