A Rhodri Williams try and the boot of Josh Lewis had got the Welsh side off to a fast start, but ultimately it was the Saints who came out on top.
They scored tries though Ken Pisi, Cobus Reinach and David Ribbans and James Fish added a second-half hat-trick with Wales fly-half Dan Biggar kicking a pair of first-half conversions.
In what was their first home game of the season, the Dragons had most of the early possession with scrum-half Williams lively after his try-scoring display at Ealing.
Williams found his half-back partner Lewis in the pocket and he slotted a simple drop goal to open the scoring after five minutes.
Bernard Jackman’s men were certainly up for the fight even in a friendly clash, tackling everything that moved and spoiling Northampton ball and it was Williams who was at the heart of it all.
The Wales cap is a real threat around the base and he soon made it two tries in as many games as he sniped over from close to a ruck and make it to the line. Lewis converted.
Jordan Williams was the next to bring a sizeable home crowd to their feet with a dazzling break and a missed kick to touch by Biggar summed up Northampton’s early struggles.
Out of nowhere, the English side got back into it.
A huge collision in midfield saw Northampton’s Centre Fraser Dingwall hit the floor, but the play continued and Pisi intercepted Jack Dixon’s pass to trot over unopposed.
Biggar’s conversion and Dingwall walking off the field was more good news for the visitors and it soon got even better for them with another intercept try.
Williams’ attempt to spread the ball wide was picked off by opposite number Reinach who sprinted over from inside his own half and give Biggar an easy kick.
The Dragons went into the break 14-10 down despite an encouraging display and Saints made 15 substitutions for the start of the second period.
One of the replacements, Fish, was pushed over the line when the game resumed and Biggar’s back-up James Grayson put the Saints 11 points clear.
Dragons then followed their opposition with mass rotation, but it was Saints who were showing them how to be clinical when it mattered as their forwards began to get on top.
Another pushover try for Ribbans which Grayson converted effectively ended the game as a contest.
Dragons introduced Wales centre Tyler Morgan for the final quarter, but the Saints’ dominant driving maul saw Fish complete his treble late on with two more converted efforts.
Grayson nailed both kicks for what was in the end a one-sided scoreline.Â
