Marcus Harness’ 28th-minute goal earned the Blues a 1-0 FA Cup win over the Southern League Premier South outfit who compete in the same division as Gosport Borough.
The size of the scoreline reflected a lacklustre Pompey display at times, particularly in the second half.
And a frustrated Cowley admitted their performance in the second period was ‘well short’ of his standards.
He told The News: ‘We take the positives of the win, the clean sheet, and the fact we are in the next round.
‘In the first half we had some good play, probably up until the final action, and then the decision or the execution wasn’t quite there.
‘I didn’t like us in the second half. I didn't like the energy, the intensity, the aggression or purpose we played with.
‘We had control in the whole game, but should find the second goal. We didn’t have the ability to do that and the longer the game goes on the harder it gets.
‘I didn’t like the way we approached that second half. It was well short for me.
‘I told the players that, it’s my job. I expect them to take it in, they need to because my standards, our standards, have to be much better than that.
‘We had lots of chances, I would expect to have lots of chances, and we probably lacked a bit of quality in the final decision and the final action.
‘I will always come out and tell you the truth, if I think they played well I will tell you.
‘I know everyone gets caught up in the result, but it’s always the process and if we are going to keep it real then I am not going to hide, I am going to tell you.’
Harrow warranted the post-match applause received from some home supporters among the 6,869 crowd at Fratton Park.
And Cowley also praised the visitors’ display against a strong Blues starting XI.
He added: ‘These games are not tactical. There’s a big difference between the quality of players and that’s no disrespect to Harrow Borough.
‘I thought they were a brilliant advert for non-league football and their manager Steve Baker should be incredibly proud of them.
‘They have won 13 of their last 15 games, it doesn’t matter what level that is, you've got to be a good team, so credit to them.’
A message from the Editor, Mark Waldron
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