Doncaster grafted to 1-1 draw at Fratton Park after taking a first-half lead through Mallik Wilks against Kenny Jackett’s side.
McCann believes his side came on strong after a slow start, and then contained the Blues well when they levelled through Omar Bogle after the restart.
He told www.doncasterfreepress.co.uk: ‘I thought we probably deserved to come in at half time even though they probably had more possession than us and we probably started the game a bit slowly.
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‘Once we got Matty Blair and Herbie Kane on the front foot we got a grip on the game for the last 15 minutes of the half.
‘Second half, I knew they’d come on strong. They made a change and went two up front.
‘When we conceded, I thought we were excellent, I thought we controlled the game, our three was outweighing their two and it forced Kenny Jackett to take a forward off. From there the game petered out.
‘Their keeper has made a couple of excellent saves from Marquis and May, one going for the top corner and the other from the bottom.
‘On the balance of the play I think it was a fair result.’
McCann felt he made positive changes after the break as he sent on Alfie May, Tommy Rowe and Ali Crawford in search of a result.
The former Northern Ireland international thought that was a success as praised Wilks’ goal.
He added: ‘We were positive, we were positive with our changes.
‘We wanted to try to get a bit of pace and legs into the team for the reason for the changes we made last week.
‘I thought it worked to a certain degree. We probably didn’t have the control we’ve had in other games with James Coppinger or Kieran Sadlier, a clever player like that.
‘The plan was to try to get people in behind their back four and it was perfect when Mallik got the goal.
‘I thought it was a perfect goal, something we’ve worked on with Mallik. It’s about breaking quickly on transition and getting in behind them. It was a great finish from Mallik.’