A Jekyll and Hyde performance saw Fleetwood surpass their 74-point target in a game of contrasting halves.
Town’s dominance in a sparkling first-half led the home faithful to boo off their team after goals from Bobby Grant and Ash Eastham gave Town a 2-0 cushion at the break– but it should have been more and Town nearly paid the price for not putting the Posh to the sword.
A rejuvenated home side then came out fighting as Craig Mackail-Smith pulled a goal back and setting up a nerve-wracking grandstand finish.
But Town stood up strong under pressure to pick up another three points to retain the six-point gap on seventh-placed Southend and move within four points of second-placed Bolton, who visit Oldham today.
Rosler made three changes to the side that lost 2-0 at Oldham. Eastham, Amari’i Bell and Kyle Dempsey returned to the starting line-up in place of the injured Cian Bolger, with Markus Schwabl and Martyn Woolford moving to the bench.
Fleetwood showed their intent from the off, with Ash Hunter dancing towards goal and stinging Luke McGee’s palms with a fierce effort.
The pitch was a vast improvement on last weekend’s chewed up Oldham turf and Town played their natural free-flowing passing game.
But Posh nearly took the lead despite Town’s dominance, with Craig Mackail-Smith curling the ball straight at Alex Cairns.
Defence-splitting runs from Bell and Dempsey saw firstly Grant and then David Ball waste great chances but Town were clinical at the next attempt. Bell sent Ball in on the left of the box and he unselfishly squared the ball to Grant who tapped the home in the 25th minute.
Town had two huge chances to increase their lead as Peteborough continued to fall apart, with Ben Davies and Nathan Pond going close from corners .
Manager Grant McCann had reacted angrily to accusations the Posh players were already on the beach after their 1-0 defeat to now relegated Coventry last weekend, but their defence certainly appeared to have their sombreros on as they allowed Town’s deflated attack to rebuild their confidence.
After more unsuccessful attempts from Grant and Bell, Posh crumbled once again with George Glendon the magician on the right flank. He put the ball on a plate for Eastham to tap in his second of the season in the 42nd minute.
Fleetwood’s dominance was evident from the boos that echoed round London Road at half-time as the home faithful showed their dismay.
It looked like goals would flow after the break but the pressure of a promotion chase began to affect Town.
After an electric first half, the start of the second was dull until a penalty appeal sparked the game back into life as Peterborough upped their game.
As Mackail-Smith collided with Cairns , it looked like referee Eddie Ilderton would point to the spot but he waved away the claim.
The decision riled the home support but Posh got their goal moments later as Ash Hunter lost the ball on a counter. Marcus Maddison stormed down the left and whipped in a peach of a cross that Mackail-Smith poked home in the 68th minute.
They nearly levelled in the 83rd minute but Cairns pulled off a sensational reaction save to thwart the unmarked Mackail-Smith in the six-yard box after Smith had outfoxed Bell on the right to whip in a tantalising cross.
Like Peterborough in the first half, Town crumbled at the back under pressure but Cairns did enough to deny the lively Mackail-Smith from another cross. At the other end, McGee denied Wes Burns a first league goal of the season as he pounced on Ball’s chip into the box.