The Pumas revived memories of their 30-16 win at the Millennium Stadium in 2001 with second-half tries from Juan Imhoff and Gonzalo Camacho enough to see them to another famous victory.
Knoyle admitted the defeat was disappointing but believes Rob Howley’s side can bounce back in next Friday’s clash with Samoa.
“It’s disappointing, that’s not what we expected,” he said.
“We prepared really well but it’s unfortunate the bounce of the ball just didn’t go our way.
“It was difficult as the minute we started to build momentum we’d lose the ball or we’d knock on or turn it over so it was difficult to build our game.
“That’s the way it is. We’ll look over it on Monday and get on with it. You can’t dwell on the past so we’ll come in on Monday and look forward to the remaining games.”
Given the chance to start ahead of Mike Phillips, Knoyle saw Wales fail to score a try with only four penalties from Leigh Halfpenny to show for their efforts.
“Personally I felt good and got to the breakdown alright but we didn’t go through enough phases to cut them down and move them around,” added the Scarlet.
“We’ve got to stay positive and pick each other up on Monday and put our best foot forward. We’ve just got to work hard and give it everything we’ve got.
“From what I can remember on the whole, it (the platform) was good. We did work hard but unfortunately a couple of errors in our game where we didn’t keep hold of the ball cost us.”
Following the surprise defeat, Wales face a short turnaround ahead of their clash with Samoa next Friday night. And Knoyle believes Wales are more than capable of bouncing back with a win.
“To be fair I think we perform even better under pressure so I think we’ll go back to the drawing board,” he said.
“At this level there’s no easy teams. You’ve got to do your homework and the little things off the field that make things happen.
“I’m sure we’ll get things right next week.”
