For the second week in a row promotion-fancies Posh tackle one of the favourites for relegation.
And the problems Posh had at Cheltenham last weekend will stand them in good stead for the visit of the Shrimps to the Weston Homes Stadium.
"We prepared well for Cheltenham,” Posh manager Grant McCann insisted.
"We knew it would be a tough game against a side good at home, but just how good Cheltenham were in that first-half took us by surprise and I mean all of us not just the players.
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“Their front two Dan Nlundulu and Alfie May were a real handful and we had to deliver an excellent second-half performance to get the win. Cheltenham had been very good themselves in the first-half.
"We can expect similar problems on Saturday. We will need to start the game better, but we will also need to be patient.
"Morecambe have a deadly striker in Cole Stockton and they have wide players like Ashley Hunter who will get up and down the flanks with pace.
"They like to play in transition so we will have to be accurate with our passing to get past a very likely low block.
"Every game in League One has danger and this one is no exception.”
Morecambe opened their League One season with a creditable 0-0 home draw with Shrewsbury.
McCann would not be drawn on which formation Posh will play after a half-time change from 4-4-3 to 3-4-1-2 at Cheltenham transformed his side’s fortunes.
There will be one definite change to the starting line-up following the departure of Sammie Szmodics to Blackburn.
Summer signing Ben Thompson, who played well at Cheltenham after coming on as a half-time substitute, is favourite to replace him.
"It’s good to know we have versatile players who are comfortable in more than one formation,” McCann added.
“And they have proved they can switch systems very effectively during a game.
"I didn’t expect to have to make the change we did at half-time, but the players reacted very well.
"I was very pleased with them.”
Experienced defender Nathan Thompson will return to the Posh squad after missing the Cheltenham game with a knock.
But forward Kwame Poku faces another week on the sidelines with a calf strain.