Tony Pulis' side had matters all stitched up by 60 minutes when Ricardo Fuller scored his side's third.
However, City suddenly took their foot off the accelerator and let the Seasiders back into the game and the Seasiders were unfortunate not to pick up a late equaliser.
City always had the extra pace and sheer size to bully Blackpool out of the game particularly with their dominance in the air.
They were confident enough to ride an early Blackpool goal scored on 14 minutes by midfielder Mike Flynn.
City failed to clear what looked like a harmless free-kick and the ball fell to Flynn who hammered home from 20 yards.
Blackpool's inability to defend set-pieces cost them dear in the run up to half-time.
On 36 minutes a free-kick from Liam Lawrence found Fuller unmarked at the far post and he took his chance well from a narrow angle.
Four minutes later Lawrence again provided the delivery - this time a corner - and Leon Cort headed home from five5 yards out.
Fuller's second on the hour came from a clinical finish after he outstripped the home defence and carefully drew the Blackpool keeper from his line before scoring from 15 yards.
Blackpool battled back and with two minutes of normal time to go Shaun Barker headed home an Andy Walsh corner.
There were five minutes of added time and City survived chances which fell to Wes Hoolahan and Andy Morrell to take another crucial three points.