Pompey had to remain patient to break down struggling Forest Green in their last home game at the start of the month.
And John Mousinho expects an equally tough challenge when Morecambe head to the south coast on Easter Monday.
Time is running out for the visitors to climb out of the relegation zone and avoid dropping into the basement.
But Mousinho knows his side will need to find a way past the Shrimps in order to keep their play-off hopes alive.
The Blues boss said: “We saw on Friday that MK Dons were set up to stop us playing – which is something we take as a compliment.
“I’m sure it will be the same with Morecambe on Monday and that is going to ramp up the pressure on us.
"It’s a game we’re probably going to have to win because the gap has now opened up slightly, but it’s not insurmountable."
“We have to find a way to deal with that and win the game because we obviously want to collect all three points.
“With some of the players they have and a few of their previous results this season, we know they are a good attacking side.
“It’s a game we’re probably going to have to win because the gap has now opened up slightly, but it’s not insurmountable.”
Marlon Pack made his first start in almost two months in the 1-1 draw at Stadium MK after recovering from a knee injury.
Mousinho said: “He got through the entire 90 minutes and we weren’t sure he was going to be able to do beforehand.
“Marlon had a big shift on after we went down to 10 men and it’s something we have to manage, but his fitness looked really good.”