But the Blues head coach admitted the 3-3 scoreline stings.
From that point, the woodwork and Craig MacGillivray rescued the visitors as Accrington surged forward for the winner.
Nonetheless, Marquis’ stoppage-time bicycle kick appeared to have secured Pompey a crucial vital in the play-off hunt.
Then, five minutes into time added on, MacGillivray saved – and the ball ricocheted off Marquis’ shins for an own goal.
A heartbreaking end for Pompey in an eventful game of football.
Cowley told The News: ‘We are hugely disappointed.
‘Once you score the winner in injury time, if you want to be a good team you have to see it out.
‘It was a roller coaster of a game and we had two great chances in the first half, gilt-edged opportunities, and we didn't take them.
‘We came in at half time, we speak the truth, which I think is always the right thing to do.
‘I was pleased with the second-half response, I thought the boys showed character, determination and grit and resistance.
‘I thought they showed togetherness and did really well to get into the game.
‘I am proud of the way they came back into the game. I’m just bitterly disappointed that we haven’t been able to see it out.
‘To say it stings is an understatement. But this is football, what we have to do is get over the disappointment.
‘We have a game on Saturday and are still fighting.’
The point lifts Pompey into sixth place with two matches remaining.
Yet Cowley was clearly disappointed with many aspects of the Accrington draw, particularly how his side coped defensively.
He added: ‘We are hugely disappointed with the goals we conceded. Although for the first, you have to give credit for a brilliant goal.
‘We didn't do well enough in the first half, for 35 minutes it was a very tight game.
‘From 35 to 45 minutes was unacceptable from us, we got outfought, outworked and outrun and that can never happen, ever.
‘The second goal was really poor, we didn’t defend our box anywhere near well enough all night.
‘We have to take responsibility for that.’
A message from the Editor, Mark Waldron
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