There were very few chances during the opening 45 minutes on the Lancashire coast.
The deadlock was eventually broken by the away side eight minutes after the restart when Korean midfielder Kim Bo-Kyung turned in a pass from Aron Gunnarsson from close range.
Just three minutes though, league leaders Cardiff were back in front. Tommy Smith collected possession on the edge of the Blackpool box and the former Watford striker sent the ball into the top right-hand corner of the goal.
Ince tried his luck from distance on a couple of occasions as Blackpool looked for a second equaliser, but Marshall was able to hold both efforts.
Despite coming under some pressure in stoppage time, the visitors held out and as a result are now 10 points clear at the top of the Championship.