Pulis said: "I am desperately disappointed to get beaten in the third round of the FA Cup. The game wasn't a classic, but we knew it wasn't going to be.
"Up until they got the goal, I thought we were OK. I couldn't see them being a threat to be honest, but as soon as they scored the goal, they deserved to win the game from that point onwards.
"We made a lot of changes, but we still had players out on the pitch who I think are good enough to get us the result.
"One or two haven't performed to their maximum, but you can't take credit away from what Hartlepool have done. In the second half, they were better than us.
"It is probably my worst performance in the FA Cup as a manager. I think it is the first time I have gone down to a team lower down in the leagues and lost in the FA Cup."