Gabriel Martinelli scored his first hat-trick for Arsenal as the Premier League leaders beat second-tier strugglers Portsmouth 4-1 to reach the FA Cup fourth round.
Fired-up home fans created a raucous atmosphere from the first whistle and were rewarded with a shock early opener.
Following good work from Harvey Blair down the left, Conor Chaplin's initial effort was only parried by Gunners goalkeeper Kepa Arrizabalaga, leaving Pompey striker Bishop to slam home on the rebound and claim his first goal since August.
Arsenal were only behind for five minutes, though, as Arsenal levelled with their first of three goals from corners.
Portsmouth were unable to deal with the set-piece delivery and the ball eventually went in off home player Andre Dozzell.
Martinelli put the visitors in front when he glanced in Noni Madueke's corner in the 25th minute and then hit the post soon afterwards from close range.
Madueke put a penalty wide just before halftime to keep Portsmouth in contention, but Arsenal eased away after the break as Martinelli converted from a superb pass by Gabriel Jesus.
He completed his hat-trick with a header as Portsmouth were again unable to defend from an Arsenal set piece.
Arsenal have now scored 17 goals from corners this season.
Willy Gnonto and Ao Tanaka scored quickfire second-half goals to help Leeds United hit back for a comfortable 3-1 win at Derby County in the third round of the FA Cup.
Gnonto and Tanaka struck in the space of four minutes to take the wind out of Derby's sails after the home side had led at the break through Ben Brereton Diaz and James Justin added Leeds’ third in added time.
Joel Piroe’s first-half penalty was saved shortly before Derby took the lead against the run of play and the threat of an upset was short-lived as Leeds dominated the second half.
Taty Castellanos scored an extra-time winner as West Ham avoided an embarrassing FA Cup exit by edging past QPR 2-1.
The Argentinian was brought in for £26million from Lazio last week in a bid to salvage the Hammers' terrible Premier League season.
That may yet prove beyond him, but Castellanos did at least take their FA Cup campaign beyond the third round with his first goal for the club.
Richard Kone had earlier cancelled out Crysencio Summerville’s opener as Rangers briefly threatened a result which would have shocked even the most ardent Hoops fan.
Ollie Bostock kept his cool to hammer home the winning penalty in a dramatic shoot-out win at Swansea to bring to an end West Brom's run of 10 successive away defeats and see his side reach the fourth round.
Having set up a goal for Jed Wallace at the start of the second period of extra time to give his side a 2-1 lead, he hit the target following three successive misses to make it 6-5 in the shoot-out after the teams had been locked at 2-2 after extra time.
