The hosts lost Jordan Rhodes just before half-time following an aerial challenge on Joe Rafferty, with the red card looking a tough soft.
The Blues subsequently hit the post three times, yet that masks a fitful performance from John Mousinho’s men who failed to press home their numerical advantage.
A goalless draw means Pompey’s lead at the top of League One is cut to five points – and here are our player ratings...
13. Owen Moxon - 6
(Replaced Myles Peart-Harris on 46 mins) Deservedly picked up a booking for an ugly challenge on Beesley and one left-foot shot drew a decent save from the goalkeeper. Photo: Jason Brown
14. Christian Saydee - 7
(Replaced Callum Lang on 56 mins) A couple of great runs in an attempt to break down Blackpool's resilience. Retains the ball so well. Photo: Jason Brown
16. Portsmouth forward Paddy Lane (32) during the EFL Sky Bet League 1 match between Blackpool and Portsmouth at Bloomfield Road, Blackpool, England on 9 March 2024.
Paddy Lane on the attack for Pompey at Blackpool. Picture: Jason Brown/ProSportsImages Photo: Jason Brown