Lee Brown has helped avoid an upset against Maidenhead, Harrogate and Altrincham in the past couple of years.
And Pompey will now be seeking to sidestep another Emirates FA Cup banana skin at Fratton Park this weekend.
National League outfit King’s Lynn – who were promoted last season – are the visitors for a second round tie.
It is a first competitive meeting between the sides and Brown knows that the Blues will have to earn their place in the next stage.
The defender said: “You’ve got to stay professional. I’ve been knocked out before against non-league sides and it’s never a good day.
“But it does happen and so it’s up to us to make sure we apply ourselves and that everyone does their job.
"There’s obviously the carrot of reaching the third round – as there is for every side – but you can’t get ahead of yourself."
“They’re not like normal league games and the opposition are out to kill the big dogs who play in a higher league.
“So you’ve got to be able to stand up to that and find a way to go through on the day because nobody wants to be on the end of an upset.
“There’s obviously the carrot of reaching the third round – as there is for every side – but you can’t get ahead of yourself.”
Brown is currently battling with Bristol City loanee Cam Pring for the left-back slot, with each of them starting one of the past two matches.
He said: “Cam’s a great full-back – I’m sure there will be times when he’s in the side and then other times when it’s me.
“It’s the same as it was when Steve Seddon came in last season. This is a squad game and you’ve got to respect what the manager decides.
“I’ll be the first to encourage Cam if he’s playing, as I did when we played Crewe last Saturday, and I know it’s the same with him.”