FA Cup fourth round: West Brom held, Arsenal through, Shrewsbury spring upset

West Brom were held by Peterborough and Shrewsbury sprung an upset but Arsenal are through to the fifth round of the FA Cup.

Tony Pulis's side looked to have avoided an awkward extra fixture but though Saido Berahino scored his second of the game (84) to restore the Baggies' advantage against League One Posh, Jon Taylor's response two minutes later means the Premier League side must head to London Road.

Bournemouth and Watford were facing replays of the their against lower-league opposition before striking late to oust Portsmouth and Nottingham Forest respectively.

League Two Portsmouth had threatened the day's big upset after taking the lead against the Cherries - 57 places above them - but Josh King (71) cancelled out Gary Roberts' opener and then Mark Pugh (83) struck to settle an absorbing contest between the south-coast sides. 

Forest, meanwhile, were moments from forcing a trip to Vicarage Road only for Odion Ighalo to come off the bench and see Watford through with three minutes to spare.

Shrewsbury, however, did stun higher-league opposition as Jack Grimmer's injury-time winner earned a 3-2 win over Championship promotion-chasers Sheffield Wednesday.

Lewis McGugan's double was cancelled out by goals from Jean-Louis Akpa-Akpro and Shaun Whalley, before Grimmer ensured the hosts' progression in dramatic circumstances. 

Holders Arsenal stayed on course for a third successive FA Cup success but were made to work for their place in the next round by Burnley.

Sam Vokes cancelled out Calum Chambers' opener but Alexis Sanchez made a timely impact, scoring the winner on his first start since November.

Kelechi Iheanacho made the most, too, of his start for Manchester City, hitting a hat-trick in a 4-0 rout of Aston Villa that also saw Raheem Sterling find the net.

Crystal Palace emerged triumphant from their own all-Premier League affair, Wilfried Zaha's 17th-minute strike proving enough to see off Stoke. 

Oxford United had shocked Premier League Swansea in the last round but found Championship opposition in the shape of Blackburn a tougher ask, Ben Marshall (2) and Tony Watt sealing a comfortable 3-0 win for the Lancashire side.  

It was a similar story at Bury, where Chuba Akpom fired a treble of his own to send Hull City through with minimum fuss.

Leeds, meanwhile, edged past Championship colleagues Bolton thanks to first-half goals from Souleymane Doukara and Toumani Diagouraga, while Reading saw off Walsall 4-0 through goals from Hal Robson-Kanu, Matej Vydra (2) and Danny Williams.

Tottenham had earlier become the first team to book their place in the pot for the next round, brushing aside League One Colchester 4-1.

Mauricio Pochettino made seven changes but Nacer Chadli's double, plus goals from Eric Dier and Tom Carroll - Ben Davies' late own goal the only blot - ensured smooth progress.

London rivals Chelsea will hope to join them when they take on MK Dons on Sunday, while Everton must overcome Carlisle to book their place in Sunday's draw.