Williams made a devastating contribution to New Zealand's 36-0 trouncing of Australia's Bledisloe Cup hopes at Eden Park on Saturday, scoring one try after missing the last two tests.
Kerevi was one of the defenders he minced on his charge for the try line. All Blacks coach Steve Hansen will have to pause for thought before he starts crossing out names on New Zealand's World Cup squad list.
And after a fortnight of savage criticism from sections of New Zealand media, who accused him of being a fragile narcissist for hitting back at his critics, Williams let his rugby do the talking.
"All that chat is disappointing because he's given so much for the jersey. He's an outstanding player," Kerevi said.
"I was really happy that I got to play him tonight, I don't think I've got to play him. . . he was on a list that I had to play all the centres that New Zealand's produced. They're the best team in my eyes and, always trying to be the best myself, I'm trying to compete with the best.
"It was really cool to play him. I thought he played outstanding."
Hansen also praised the 52-test centre, who battled a run of injuries but was called up after injury hit the New Zealand midfield. The All Blacks coach moved Anton Lienert-Brown to 13 and handed Williams the jersey over Ngani Laumape.
"Sonny's been under a lot of pressure, he hasn't played a lot of games because of his injury," Hansen said after the game.
"He's had a run of games and played well tonight. When we needed someone to go direct, funnily enough, the ball would go into his hands and he'd do that.
"We're pretty happy with how he played."
Australia flew home on Sunday with an all too familiar feeling, having had little in answer when the All Blacks came out swinging.
The match was an arm wrestle for the first 20 minutes but after Christian Leali'ifano missed two shots at goal and New Zealand soaked up pressure on their try line before turning Reece Hodge's overrun into their first try, the game unravelled.
"They're a really hard team to stop when they get that momentum going. We weren't good enough and we have ourselves to blame," Kerevi said.
"We really wanted to get that win for our people and we're disappointed in the result but we're grateful for the support, not just from last week, but the weeks before that."
As Australia's vice-captain, the 25-year-old said the Eden Park disaster did not negate the gains of the past four weeks, which featured victories over New Zealand and Argentina and a tough loss to South Africa.
"I feel there's massive growth, not just on the field but off the field as well," Kerevi said.
"I think it comes back to believing in what we're doing. Ticking each day off, ticking each box and believing in the guy next to us, building through towards something that is bigger than us that's coming up, which is the World Cup. We've all got our eyes on that and every nation will be doing little things to get that stuff right."