Published: 00:00, 28 April 2014
| Updated: 08:14, 28 April 2014
Charlton missed the chance to clinch Championship safety when they lost 3-1 at home to in-form Blackburn on Saturday.
A win against Watford at The Valley on Tuesday night would be enough to survive, otherwise their season will be decided on the final day at fellow strugglers Blackpool.
The Addicks, two points clear of the bottom three in 19th place, fell behind to a Rudy Gestede header from Joshua King's cross after 26 minutes.
Marvin Sordell, who scored a hat-trick in the Easter Monday win at Sheffield Wednesday, had a chance to level just before half-time but saw his penalty saved by ex-England keeper Paul Robinson.
Blackburn extended their lead on 51 minutes with Michael Keane heading home a Craig Conway free-kick.
Sordell did pull a goal back three minutes later with a strike from the edge of the box.
But Rovers made sure of the points through Tom Cairney on 64 minutes after Jordan Rhodes' shot was blocked.
Addicks boss Jose Riga said: "We know what we have to do against Watford. We know that destiny is still in our hands and I hope we will do the job in the next game and not wait for the last one. We have to do what we have to do.
“What gives me the confidence is what the players already have done in the past. We have beaten big teams away like Leeds and Nottingham Forest and we made a good result against Bournemouth."
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