The Pumas had to wait until Sunday to face England in Round 2, while Wales hosted New Zealand the day before and lost 55-23.
“The start of the game didn’t help. You can’t start like that against New Zealand – we gave them a big head start,” said Williams.
“We got back into the game quite well, but we gave them too many easy entries into our 22. You can’t do that because they are so clinical.
“They took pretty much every chance they had. Against New Zealand you have to score tries and unfortunately, at points in the game, we didn’t.”
The Cardiff Rugby scrum half was in top form once again and put in the kick over the top of the All Blacks defence that led to skipper Justin Tipuric’s try. That was Tipuric’s 11th try for his country, bringing him level with Scott Quinnell in the list of Wales’ leading try scorers among the forwards.
WRU National Representative Colin Charvis leads the way with 22, while current Wales team manager Martyn Williams is second with 14.
Despite the scoreline against the Kiwis, Williams took positives from the way in which Wales twice fought back to within one score having trailed 17-0 so early on.
“We’ve got a lot to work on and there were a few positives. We fought our way back into the game, finished the first half well and started the second half well,” he added.
“I don’t want to make any excuses, but New Zealand might have had a little bit of a head start with their extra game. That’s the nature of the game, we can’t do anything about that. Hopefully, we can just get better now.
“Argentina beat the All Blacks in the summer and they are a very passionate nation. When you play against them you have to front up. Every game in this series is going to be physical, so we will recover well and be ready for next week.
“It was a big step up from playing in the URC, you could see that in the level of the game. New Zealand are one of the best teams in the world, arguably the best.
“You always want to start well but it might take a game or so to get fully up to speed. This won’t dent our confidence. We were confident we could beat them, but it wasn’t to be.
“We’ll work hard on Monday and hopefully get it right for next weekend.”
