The Weston Homes Stadium was the scene of a 3-2 victory for SWANSEA City as they defeated PETERBOROUGH United.
Michael Obafemi's low shot was the difference at the break.
Jack Marriott came off the bench and scored just seconds after Sammie Szmodics swept in.
Piroe's 17th goal of the season was the difference as Obafemi leveled with a crisp volley.
With nine games remaining, the team is seven points adrift of safety.
Their winless league run now stands at 15 games, with Grant McCann still looking for his first triumph since taking charge of the club for a second time last month.
A fifth away league win of the season helped propel SWANSEA up to 15th.
There were doubts about whether the game would go ahead because of the heavy rain in Cambridgeshire, but the referee decided the surface was safe and the tricky conditions didn't seem to affect the performance.
Russell Martin's team took control from the beginning, with Peterborough seemingly content to sit deep and hope to strike on the counter.
Obafemi was the first to threaten, forcing a save from David Cornell and then lifting over the bar to meet the centre.
Cornell pushed the ball around the post after Piroe curled goalwards from 20 yards.
The team that had not won a league match since 11 December looked like a team that was going to be hard to beat, and the goal that was scored by Obafemi was the one that deserved to be scored.
The hosts had no choice but to take a bolder approach after the break, and a willingness to commit more players forward brought almost immediate reward.
Szmodics scored his first-ever goal after Ricky-Jade Jones' pace took him beyond Cyrus Christie and a perfect cross teed him up.
Cornell came off his line to deny the Austrian a first goal in English football when Paterson fed him in the box.
Jones, who had been their best player, was forced off with a shoulder injury.
Within seconds of entering the field, his replacement scored.
When Kyle Naughton picked up possession in his own box, he should have been able to escape, but his mishit clearance presented Marriott with his first touch.
The forward rolled a shot inside the far post to put Peterborough ahead.
Obafemi scored after Christie had headed a deep cross against the post to give the visitors a response.
The one-timeSwansea goalkeeper could do nothing to stop Piroe from scoring as the blocked shot fell to him and he stroked home from 15 yards.
Grant McCann is the manager of Peterborough.
The first half we didn't get against the ball enough. We let them dictate most of the first half. We knew what they were going to do, but we didn't get the press right.
We didn't jump to the ball because we sat too defensive. At times, we end up like a flat seven or eight. You need people to push people on at times.
We got ourselves back into the game, played a bit more on the front foot and took the lead through Jack.
You are hoping that we can manage the game. We sat back in shape. Maybe it is a confidence, maybe it is know-how, maybe it is a little bit of game management. That probably showed.
Russell Martin is the head coach.
I am still trying to digest the first 15 minutes of the second half, which I am really disappointed with. I can't believe the game turned into that. The players were brave to get control back. We should be out of sight at the half-time break.
I will continue to be proud of this group for what they are doing, but for 15 minutes we were nowhere near.
We are in the league because of that. We are capable of producing some amazing moments on our day. There is a big gap between when we are good and not. You saw that in one game.
I have decided not to speak in the dressing room tonight. I said well done for showing some courage but we will discuss it on Friday and we will learn about the game.
Formation 3-4-3.
23Ward42Fuchs18Norburn24Mumba7Szmodics9Clarke-Harris17JonesFormation 3-1-4-2.
4Downes26Naughton5Cabango23Christie7Smith12Paterson13WolfThe match ended with Peterborough United defeating Swansea City.
The second half ended with a score of 2, 3 and 2.
The yellow card for a bad foul was shown to Joël Piroe.
Foul by Joël Piroe.
A free kick is won in the defensive half.
An attempt was missed. Josh Knight's shot from a difficult angle and long range on the left is close, but misses to the left. The assistance was given by Bali Mumba.
Kyle Joseph had a foul.
A free kick is won in the defensive half.
Kyle Joseph had a foul.
Oliver Norburn won a free kick in the attacking half.
There is a substitution forSwansea City. Jamie Paterson was replaced by Jay Fulton.
The defensive half is where Wolf won the free kick.
The person is Joe Ward (Peterborough United).
Goal! The teams were: Peterborough United 2,Swansea City 3. The left-footed shot from the centre of the box was taken by Joël Piroe. Hannes Wolf assisted.
The attempt was blocked. The left foot shot from Ntcham was blocked. Cyrus Christie assisted.
The attempt was saved. Cyrus Christie's shot from the right side of the box was saved in the centre of the goal. Ben Cabango assisted.
Flynn Downes won a free kick in the defensive half.
Foul by Jeando Fuchs.
Jamie Paterson is fromSwansea City.
A free kick is won by Joe Ward.