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England winger Ben Cohen and 21 year old Ian Vass struck with superb tries to see off the spirited challenge of Cardiff.

The Welsh side had competed well in the first half but Cohen burst over just 48 seconds after the interval to put them firmly on the back foot and they could not recover.

We made some improvements in our set-pieces and the driving play was good Northampton coach Wayne Smith

Vass, a replacement for injured scrum-half Matt Dawson, had also got in on the act with an individual try in the first half.

Two penalties from Iestyn Harris gave Cardiff an early 6-0 lead.

But fly-half Paul Grayson responded and then Northampton's first try followed when number eight Mark Soden was driven over by his pack.

Grayson missed the conversion but made no mistake after Vass had dummied and side-stepped his way through the Cardiff defence.

Cardiff were the underdogs in terms of physical power among the forwards but the pace of their backs always looked like posing a threat.

Full-back Rhys Williams cut the deficit to 15-11 in the 24th minute as he showed Cohen a clean pair of heels on a diagonal run to the line.

Harris missed the conversion and was then also off-target with a long-range penalty.

They are one of the best teams in the country and we weren't far behind them Cardiff player-coach David Young

As the second half began, a drive by flanker Andrew Blowers and a neat piece of handling and perfectly timed pass from Grayson sent Cohen bursting between the posts.

Grayson added a penalty to the conversion and Northampton never looked back.

The one blemish on Cohen's match was when he was sin-binned in the 72nd minute for a high challenge on Cardiff replacement Richard Smith.

Northampton: Nick Beal; Jon Sleightholme, Chris Hyndman, John Leslie, Ben Cohen; Paul Grayson, Ian Vass; Robbie Morris, Steve Thompson, Chris Budgen, Rob Hunter, Steve Williams, Andrew Blowers, Budge Pountney (capt), Mark Soden.
Reps: Dan Richmond, Tom Smith, Jon Phillips, Simon Hepher, Johnny Howard, Mark Tucker, Oriol Ripol.

Cardiff: Rhys Williams; Nick Walne, Jamie Robinson, Matt Allen, Craig Morgan; Iestyn Harris, Ryan Powell; Peter Rogers, Andrew Lewis, David Young, Heino Senekal, Adam Jones, Rob Appleyard, Dan Baugh, Martyn Williams (capt).
Reps: Tim Payne, Lewis Collins, Dan McShane, Emyr Lewis, Richard Smith, Nick Robinson, Anthony Sullivan.

Referee: Iain Ramage (Scotland).