Williams said in his Rugby Paper column that Wales had always been slow starters of their autumn campaigns.
"The All Blacks won't be starting slowly in Cardiff. They are firing on all cylinders after winning the Rugby Championship, and they've been playing some seriously impressive rugby.
"Yes, they lost to South Africa in their last game (what a Test match that was!), but watching the Championship, I think Ian Foster has started to put his mark on the side.
"Look at the try Ardie Savea scored against the Springboks. That showed me the All Blacks are purring right now because it came straight from first phase.
"With the way modern-day defences are organised, it is very rare to see a team score straight from a lineout, but that's exactly what Foster's men did. Savea starts the move by lifting Akira Ioane to win lineout ball at the tail just inside the South African half.
"From there on in, the move is razor-sharp. Some might rightly question the level of South Africa's defence, but Beauden Barrett and Rieko Ioane make great breaks in midfield and Savea goes over after running a great support line.
"It's some try and a warning that Wales can't give New Zealand an inch," Williams said.
Wales would face difficulty containing the All Blacks.
"Wales will have to give them nothing behind the scrum because the Savea try shows that if you give New Zealand an inch, they will take a mile," he said.
Williams said coach Wayne Pivac faces some big calls, especially with the number of player absences for the game.
While Williams felt it would be too much to ask New Zealander Gareth Anscombe to play so soon after returning from two years out with injury, he expected Pivac would opt to play him at first five-eighths.
"I wish him all the best. I'm sure it will mean a lot to him for his Welsh return to come against the country of his birth," he said.
From the moment the Wales squad gathered, they would need to fire immediately.
"There can be no dawdling because every session in the run-up to the All Blacks' game will be vital. Wales will be behind the eight ball from the start.
"The question is, can they catch up quickly to compete with the best on the planet?" he said.