Mobbed by the crowd at the end of the game, his talents in the previous 80 minutes showed why the New Zealand Rugby Union was so keen to have him.
In his first visit to Dunedin, Williams scored the try which won the game for Canterbury, seeing off the defence on a jinking 60m run.
The former league star admitted after the game his legs were fading as the tryline came into view.
"The lungs were all right but the legs were feeling a bit sore. I think that's the furthest I've run since I was about 10," he said.
"It was a really fast game, and the ball was being moved all the time. That is definitely the most tired I've felt at the end of the game since I've started here. The ball was being moved all over the park.
"Plus maybe after only playing 40 minutes last week I was blowing out a few cobwebs."
Williams was playing centre for the first time and said that might have also been the reason he found himself so tired.
"You've got more space, and more ground to cover. I just enjoy the way we play - play expansive and move the ball around. I just want to keep my workrate up and improve each week."
Williams made some nice off-loads, and looked strong in defence, but the Canterbury attack misfired at times with too many forwards getting in the way in the backline.
Williams said Canterbury's next match, against Southland for the Ranfurly Shield, was obviously a big game, but the side would just approach it by doing a debrief of this game, and then working on eliminating errors.
And as for the mobbing by the crowd at the end of the game, Williams said it was great to have that sort of support.
"Always good to know you've got that support, especially back in your home country, that people want to get in behind you."
The presence of Williams undoubtedly led to a crowd of 6100 at Carisbrook, the biggest of the season.
A new Otago supporter - the Razorback, named after the wild pig was given its debut on Saturday, with the pig taking over from the departed Shaq as the Otago mascot.
