Pompey stayed three points clear at the top of League One as closest rivals Peterborough were thumped 4-0 by Barnsley at London Road.
Barnsley maintained their promotion challenge thanks to George Moncur's early strike, Brad Potts' double either side of the interval and Jacob Brown in time added on.
Moncur scored his opener just over a minute after Barnsley goalkeeper Adam Davies had saved Posh striker Ivan Toney's penalty.
Fleetwood stormed to their first league win in six matches by beating high-flying Doncaster 4-0 at the Keepmoat Stadium.
Ched Evans converted an early penalty after he had been fouled by Marko Marosi and headers from James Wallace and Ashley Eastham put Joey Barton's side 3-0 up at half-time.
Ashley Hunter notched the visitors' fourth early in the second period.
Sunderland got back to winning ways with a 2-1 victory at Bradford where both sides ended with 10 men.
Bradford defender Anthony O'Connor cancelled out Josh Maja's first-half opener, but Sunderland regained the lead two minutes later through Jack Baldwin.
Sunderland striker Max Power was shown a straight red card in the 66th minute for his challenge on Jack Payne, who then saw his subsequent penalty saved by Jon McLaughlin.
Bradford winger Sean Scannell also received a straight red card for his tackle on George Honeyman in time added on.
Alex Gilliead headed the only goal as Shrewsbury secured their second league win of the season against 10-man Accrington.
Gilliead struck midway through the second half after Accrington goalkeeper Connor Ripley had been sent off for his professional foul on Lee Angol early in the first period.
Walsall substitute Kieron Morris struck in stoppage time to clinch his side a 1-0 win at Bristol Rovers and two late goals from Amadou Bakayoko secured Coventrya 2-1 win at Charlton.
Lyle Taylor's first-half penalty gave Charlton the lead, but Bakayoko scored twice in the last nine minutes for the Sky Blues.
Luton made it five league games unbeaten with a 3-2 home win against Scunthorpe.
Hatters' par Harry Cornick and Elliot Lee scored either side of Lee Novak's equaliser for Scunthorpe.
James Justin made it 3-1 before Stephen Humphrys added the visitors' second consolation.
Oxford remain winless on the road this season after a goalless draw at Southend.
Rochdale twice hit back to draw 2-2 at Blackpool.
Ryan Delaney cancelled out Jordan Thompson's early opener for Blackpool.
Calvin Andrew headed a late equaliser after Blackpool had regained the lead through Curtis Tilt.
Wycombe clinched their first home league win of the season with a 2-1 victory against Burton, who remain winless on the road.
Joe Jacobson's penalty, after Kyle McFadzean's foul on Craig Mackail-Smith, and Adebayo Akinfenwa's header gave Wycombe a 2-0 half-time lead.
Burton replied through Marvin Sordell soon after the restart but the Chairboys held on.
Plymouth registered their first league win of the season to climb off the foot of the table thanks to Freddie Ladapo's second-half header in a 1-0 home victory against AFC Wimbledon.