Ben Thompson admitted Maidenhead posed Pompey problems before his crucial opener.
Kenny Jackett’s men eased to a comfortable 4-0 win in this afternoon’s FA Cup encounter.
Yet it wouldn’t be until the 43rd minute before the Blues made their breakthrough at York Road.
Thompson converted Ronan Curtis’ left-wing cross to hand the visitors the lead – with Oli Hawkins, Jamal Lowe and David Wheeler netting in the second half.
Yet before Thompson struck, Ayo Obileye provided a scare when he smashed a shot against Craig MacGillivray’s left-hand post.
And it’s Jackett’s men who now await their opposition in Monday’s second-round day.
Thompson said: ‘The first half was a bit shaky at times, they got into the game and we were on the back foot a little bit at times during spells.
‘To put the side ahead with the first goal was a great feeling and we kicked on from there.
‘The second half was a bit easier for us – and we came here and did the job.
‘Maidenhead caused us some problems, we caused them some problems and it was quite a close encounter in the first half, we were patient and got the result we needed.
‘They hit the post, they came close, who knows if that goes in it could have changed the game.
‘But at the end of the day we got the win and are through to the next round and that’s all that matters – that’s what we came here for.’