A superb finish from Jonson Clarke-Harris just before the half-hour mark was enough to give Peterborough a 1-0 Sky Bet League One victory over Wigan at the DW Stadium.
The lively striker was given too much time in the Wigan box by the home defence, and his finish was too good for Jamie Jones to keep out.
And the visitors held on for their fourth league victory in a row to put some pressure on the early pacesetters.
Wigan almost stole a point at the death, only for Kal Naismith’s curling strike to hit the far post and bounce away to safety.
Matty Palmer, making his Wigan debut after joining on loan from Swindon, was given a clattering in the early stages from Dan Butler.
And the Posh left-back’s heart was possibly in his mouth moments later when he tripped Naismith in a similar situation, with some of the Wigan players wondering about whether a second yellow might be on the way.
Naismith was quickly to his feet and sending over the free-kick fizzing across the penalty area, just in front of the onrushing Wigan attackers.
But Posh almost made the most of their opening attack, with Joe Ward firing inches wide of the near post from 12 yards.
Wigan did not heed the warning, though, and the visitors did take the lead after 28 minutes, through striker Clarke-Harris.
The lofted ball in from Butler was allowed to find Clarke-Harris in space inside the Wigan box, and the Posh man controlled with his chest before volleying past Jones.
Peterborough made an interesting tactical change 10 minutes before the interval, with Butler withdrawn after conceding another free-kick, boss Darren Ferguson possibly fearing a second yellow card was imminent.
Wigan threatened towards the end of the first period but, after showing superb skill to win himself a yard, Will Keane could not get the ball out of his feet and he was dispossessed.
Wigan required a fine save from Jones early in the second half to keep the score at 1-0 after Reece Brown tried his luck from 12 yards.
At the other end, Lee Evans had a decent shooting opportunity but saw goalkeeper Cristy Pym help his shot round the post.
It looked like Posh would keep their opponents at arm’s length for the duration but, as the clock ticked into the four added minutes, Wigan almost hit back.
Naismith did all the work down the right-hand side, cutting in and trying to find the far corner with his left foot.
But the ball always had just too much to do and found only the far post – to the dismay of the home side.