Wycombe had to settle for a goalless draw at Ipswich after missing a late penalty to extend their advantage at the top of Sky Bet League One.
Gareth Ainsworth's side should have turned one point into three, but Joe Jacobson saw his 87th-minute penalty saved by Ipswich goalkeeper Tomas Holy.
Wycombe remain five points clear but second-placed Ipswich were denied an opening goal in controversial fashion two minutes before the break.
Luke Chambers headed home Luke Garbutt's corner but referee Alan Young disallowed the goal for offside after consulting linesman Aaron Farmer.
Kayden Jackson was adjudged to have turned the ball home but television replays suggested the final touch came off a Wycombe defender.
Portsmouth beat Rotherham 3-2 in a see-saw encounter at Fratton Park.
Ronan Curtis fired Portsmouth ahead inside 60 seconds with a spectacular effort, but Freddie Ladapo equalised from close range after 15 minutes.
Pompey were back in front after 37 minutes as Ellis Harrison knocked down Lee Brown's cross and John Marquis headed home his fifth goal of the season.
Ladapo equalised from the penalty spot just after the hour-mark when Oliver Hawkins brought down Carlton Morris.
Ben Close volleyed a superb winner from the edge of the penalty area for Portsmouth after 66 minutes.
Sunderland's struggles under new manager Phil Parkinson continued with a 2-1 home defeat to Burton.
Parkinson has won just two of his 10 games in charge with the Black Cats slipping to 11th.
Sunderland took a 19th-minute lead when Luke O'Nien was brought down by John-Joe O'Toole and Aiden McGeady converted the penalty for his sixth goal of the season.
But Ryan Edwards headed an instant leveller and Liam Boyce slotted home Burton's winner from close-range after 68 minutes.
Forest Green were held 0-0 at home by Crewe as they missed the chance to go top of League Two.
Victory would have taken Forest Green above Swindon on goal difference but third-placed Crewe proved resilient opposition.
Grimsby and Cheltenham also fought out a goalless draw as the struggling Mariners' winless run stretched to 10 games.
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