It was a disappointing evening for the visitors and the home side could have found themselves one up after only 3 minutes, when Chris Marriott's diagonal ball over the top found Adrian Cieslewicz who lobbed the ball over Blues keeper Colin Doyle but defender James Fry was on hand to clear early on.
It was the hosts who played the better football throughout the first half, not allowing Blues to even have an attempt on Chris Mullock's goal in the opening 45 minutes.
After 23 minutes Saints striker Mike Wilde went close when he was quickest to react to the loose ball in the box but he fired his shot wide of Doyle's left hand post.
Three minutes later attacking midfielder Alex Darlington brought Doyle into action. After an adventurous run from full-back Simon Spender the ball fell to Darlington on the edge of the Blues penalty area but his effort was hit with no real conviction and tamely found it's way into Doyle's hands.
Just after the half hour mark to deadlock was broken. Blues defence allowed Saints left back Marriott to run with the ball from inside his own half, finishing up on the edge of the Blues area before Cielewicz played in Darlington who fired the Welsh champions into the lead.
Ten minutes later the hosts doubled their advantage, Darlington again causing problems, latching onto a long ball from centre-back Phil Baker before getting the better of Spector and setting the ball for Scott Quigley to finish from eight yards out.
Blues came out for the second half with a lot more urgency and conviction and within a minute had already threatened more than they had in the previous 45. Substitute Luke Armstrong timed his run well to get on the end of a Denny Johnstone flick but his curling 20-yard effort was pushed wide by Mullock.
From the resulting corner Charlee Adams went close but his header flashed past the far post.
Two minutes later, striker Denny Johnstone went close when his powerful header crashed against the woodwork.
On 55 minutes Blues halved the deficit, Chris Mullock's hurried and scuffed clearance went straight to Callum Reilly, who managed to quickly get the ball out of his feet, before firing his low shot past Mullock in the Saints goal.
Less than a minute later the home side restored their two goal advantage. Darlington bagging his second of the game after Greg Draper's effort cannoned back off the underside of the crossbar.
The New Saints third goal killed Blues' fightback just as it had started. Armstrong struck the post after good work from Johnstone down the right hand side and Olly Lee's free-kick was well stopped by Mullock with his feet.
Late on, it could have got worse for Blues when Darlington, a thorn in the side of Blues all evening, played in Ryan Edwards but his effort beat Doyle but not the post.
Blues starting XI: Doyle; Spector (Kelly, 58), Hancox (Moseley, 71), Fry (Cogley, 45), Adams; Webb (McGee, 45), Lee, Reilly, Truslove (Solomon-Otabor, 45); Nasseri (Armstrong, 45), Johnstone
Unused Subs: Truman
The New Saints starting XI: Mullock; Marriott, Spender, Baker, Rawlinson; Cieslewicz (Pryce, 80), A. Edwards (Finley, 45), R. Edwards, Darlington, Quigley (Ruscoe, 77); Wilde (Draper, 45)
Unused Subs: Harrison, Evans, K. Edwards, Douglas
Goals: Darlington (2), Quigley
Referee: Martin Williams