MK Dons were beaten 3-1 by Portsmouth at Fratton Park as they slipped to a first defeat in six.
Things started badly for Russell Martin’s side as a defensive error allowed Andy Cannon to grab an early opener.
Alex Gilbey equalised for MK Dons in first half stoppage time, with the midfielder scoring a rebound after seeing an initial penalty saved.
But John Marquis restored Portsmouth’s outbreak shortly after the break, and Marcus Harness struck a clincher in second half stoppage time.
MK Dons had striker Carlton Morris sent off just before the final goal, as they lost for the first time since they were beaten by Sunderland in mid-Janaury.
However, they are still without an away win since September, and their gap on the relegation zone was cut to 10 points after Tranmere Rovers scored a last minute winner to defeat Shrewsbury Town.
Portsmouth opened the scoring inside four minutes, when a loose ball allowed Ryan Williams to round Lee Nicholls and square for Cannon to tap the ball in.
Alex Bass made a save to deny Gilbey in a one-on-one, with the Portsmouth keeper also denying Rhys Healey in the first half.
An even first half saw Portsmouth have a few half-chances, but as the game moved into first half stoppage time, MK Dons drew level.
The away side were given a penalty after Healey was bundled over inside the box. Gilbey’s initial penalty was saved by Bass, but the midfielder’s rebound found the back of the net and MK Dons were back level.
However, Portsmouth restored their advantage three minutes after the restart, as Marquis was given space to turn in a cross from the Portsmouth right via a post.
Regan Poole would head wide as MK Dons tried to find an opening to get back. Healey and substitute Ben Gladwin would also come close.
But MK Dons couldn’t find a breakthrough and their task became harder when Morris was dismissed a few moments from the end. The striker was shown a straight red card for pulling down Marquis when the opposing player was through on goal.
The home side then grabbed a third and final goal as the game moved into stoppage time, as Harness evaded Lee Nicholls and tapped in to rubber stamp victory for the promotion chasing hosts.