Johnson scored six minutes from time to seal a 1-0 victory at promotion rivals Darlington, who cannot now overhaul their opponents with wins in their two matches in hand.

Second-placed Hereford kept up the pressure with a 3-1 victory at Bradford.

Theo Robinson, Dean Beckwith and Trevor Benjamin scored the goals for the visitors, who were briefly pegged back to 2-1 by David Wetherall.

Marc Joseph's first-half strike was enough to give Rotherham a 1-0 win at Notts County and lift them to third in the table.

Chesterfield climbed up to fifth with a 2-0 victory at Barnet, Adam Rooney and Janos Kovacs with the goals.

Morecambe survived the sending-off of David Artell to come from two goals down to beat high-flying Peterborough 3-2.

Posh raced to a 2-0 lead through Craig Morgan and Charlie Lee.

Artell began the fightback but his dismissal before half-time appeared to end their resistance.

Carl Baker had other ideas, scoring twice - including a penalty winner - to complete the turnaround.

Ryan Valentine saw a spot-kick saved as rock-bottom Wrexham went down 1-0 at home to Stockport.

County substitute Anthony Elding put the visitors ahead but Valentine wasted a glorious chance to snatch a point.

Second-bottom Mansfield were also undone by a penalty as Andrew Proctor secured a 2-1 win for Accrington Stanley after a frantic stoppage-time period.

Paul Mullin put the visitors ahead and Proctor made it 2-0 from the spot in time added on in an incident that saw Martin McIntosh sent off.

But home substitute Ian Holmes pulled a goal back moments later.

Ben Strevens netted a brace as Dagenham and Redbridge won 2-0 at Bury to ease their own relegation fears.

John Sutton's eighth-minute goal was enough to give Wycombe a 1-0 win at Shrewsbury, while Brentford beat Chester 3-0 courtesy of goals from Alan Connell, Ross Montague and Glenn Poole.

Glenn Murray headed a stoppage-time equaliser as Rochdale came from 2-0 down to draw 2-2 at Macclesfield.

Levi Reid and Gareth Evans put the home side in charge at half-time but Adam Rundle halved the deficit before Murray provided the late drama.

In the midday kick-off, Gary Jones came off the bench to earn Grimsby the spoils in their Lincolnshire derby with Lincoln.

Jones headed the only goal of the game five minutes from time to ease the Mariners' relegation worries and leave their opponents - who saw Scott Kerr sent off in the last minute - in deep trouble.