New Zealand were easy 60-14 winners over visiting Islanders Fiji but were far from happy with a somewhat scrappy display, particularly at the restarts and line-outs.
Cowan is however confident that Graham Henry's squad will be able to iron out their shortcomings this week.
"It was pleasing to get off on the right foot with a good win," Cowan told NZPA
"To rack up 60 points is pleasing in a Test match, but some of our fundamentals, our foundations, were still lacking in areas. But we've only had three or four training runs together, so that was expected.
"I think it's about building our game and I imagine we'll see a remarkable improvement over this week."
Loose forward Jerome Kaino said skipper Richie McCaw had identified the need to improve their work at the breakdown ahead of the clash with the world champions in Wellington.
"Fiji played really well slowing our ball down and we couldn't really get our game going effectively with the slow ball we were getting so that's a huge focus this week to be able to recycle our ball a lot better and hopefully get our game going," said Kaino.
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The entire All Blacks apparel line has been updated for 2013/14. Check out the New Zealand All Blacks polo.
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