BIG-MATCH FACTS
The tie in context
• This is the only replay that will guarantee that at least one of the three remaining Championship clubs qualify for the last eight.
Gulf in class
• Third placed West Brom are 17 spots higher than Reading, who are fifth bottom.
Fifth Round draw
• Prize for the winners will be a home tie against either fellow Championship Crystal Palace or Premier League Aston Villa in the quarter-finals.
Head-to-head
• West Brom needed a late equaliser to secure this replay.
Reading 2-2 West Bromwich Albion (FA Cup, 13 Feb)
• The home club prevailed when these two met in the league at the Hawthorns earlier this season.
West Brom 3-1 Reading (Championship, 17 Oct)
• Albion hold a six-match unbeaten home record against the Berkshire club.
• Reading's most recent triumph at the Hawthorns was 4-2 in a second round second leg League Cup tie in October 1995.
FA Cup records and best performances
• This is the third time these clubs have been paired together in the FA Cup, and honours are even at one win a piece.
• Reading prevailed most recently. The Royals needed extra time, in a third round replay at the Madejski four years ago.
The clubs
WEST BROMWICH ALBION
Current form
• Not won in three (all competitions).
• Won their last three league and cup matches at the Hawthorns.
• Roman Bednar could make his 100th start for a British club.
• Simon Cox could play against the club where he started his career.
FA Cup form
• Looking for a second successive Championship scalp, after ending Newcastle's interest in the fourth round.
• On their best run since qualifying for the semi-finals in the season before last.
READING
Current form
• Saturday's 2-0 defeat at Blackpool was their first loss in six league and cup games.
FA Cup form
• The giant-killers of Liverpool and Burnley, had not progressed beyond the third round, since reaching the last 16 three years ago.
• They are vying for a first quarter-final appearance since their club record run to the semi-finals in 1927.
Match officials
Referee: Lee Mason (Lancashire)
Assistant referees: Stuart Burt & Scott Ledger
Fourth official: Mar Haywood
Source: BBC Sport
Source: BBC Sport