Events at Gillingham, Kidderminster and Crewe elsewhere in the cup left Pompey fans nervous as to what was yet to come, but Portsmouth applied themselves well in the second half, creating a host of chances.
Deon Burton, making his first start for Portsmouth since around March 1917, worked hard and struck the crossbar twice, Sheringham and Stefanovic also came close to wearing the Seasiders down.
But, as we've seen in many a cup tie, the higher division side's improved fitness won out when, as Portsmouth fans seemed resigned to a replay at Bloomfield Road, Yakubu stepped up to ruin the Tangerine's cup dream when Blackpool's keeper Jones found Sheringham's shot too hot to handle and the Yak struck home from close range. Just to compound their misery, defender Gareth Evans was then sent off for a foul on Burton.
Portsmouth may not have impressed, but at least they are in the hat for the fourth round. Many - such as last year's finalists, Southampton - are not.