(CNN) -- Arsenal were held to a 1-1 draw by English League One side Leyton Orient in the FA Cup fifth round on Sunday.
Arsenal, who recorded a famous 2-1 win over Barcelona in the Champions League in midweek, fielded a weakened side for Sunday's fixture and looked to have done enough to win when Tomas Rosicky headed home in the 53rd minute.
But Leyton Orient battled on and were rewarded when substitute striker Jonathan Tehoue beat two defenders before striking a low drive through Manuel Almunia's legs in the 88th minute.
The winners of the replay at the Emirates stadium will face Manchester United at Old Trafford in the quarterfinals.
In the other FA Cup ties played Sunday, Manchester City thrashed Nott's County 5-0 in their FA Cup fourth round replay match at Eastlands.
Paul Ince's League One side had managed to hold their more illustrious opponents to a 1-1 draw at Meadow Lane in January, and for a time held their own against Roberto Mancini's men.
It took City almost 40 minutes to break the deadlock when Patrick Vieira opened the scoring when he headed in at the near post from a David Silva corner.
Vieira added a second just before the hour to all but kill off any hopes of a revival by County.
But City weren't finished and further goals were added by Carlos Tevez -- who rounded Nelson in the Notts County goal before sliding the ball home -- in the 84th minute. Edin Dzeko added another in the 89th minute and Micah Richards made it five in injury time.
The win sets up a fifth round tie with Aston Villa.
Bolton Wanderers have booked their place in the quarterfinals after recording a 1-0 victory at Fulham.
Croatian striker Ivan Krasnic got the decisive goal after 19 minutes with a volley past Mark Schwarzer.
Bolton will face Birmingham at St Andrews for a place in the semifinals.
Sunday's only English Premier League match saw the Midlands derby between West Bromwich Albion and Wolverhampton Wanderers finish in a 1-1 draw.
Wolves were heading for all three points after Jamie O'Hara had put them ahead after 39 minutes.
But Carlos Vela's pounced on a loose ball to tuck away an injury-time equalizer for Roy Hodgson's team.
The goal denied Wolves the chance to move off the bottom of the table, while a point lifts West Brom one point above Wigan in 17th place.