Crystal Palace set up a repeat of the 1990 FA Cup final against Manchester United after Connor Wickham's second half header secured victory over Watford at Wembley. Wickham nodded home after the hour mark to ensure Alan Pardew will lead the Eagles into the final in May, 26 years on from playing in the club's only other appearance in a domestic cup final in their history.
Yannick Bolasie gave Palace the lead after just six minutes - a goal which sparked memories of Pardew's header in the semi-final against Liverpool two decades previous - but Troy Deeney levelled after the break as he converted Ben Watson's corner. But just seven minutes later Wickham out-jumped Nathan Ake to head past Costel Pantilimon and send the Eagles through.
Scott Dann avoided being sent off for a high challenge on Odion Ighalo, who carved out Watford's best opening in the closing stages but skied his effort. Wilfried Zaha and Wickham could both have made Palace's passage into the final far more comfortable, but it mattered little as the club secured a return to Wembley for the third time in as many years.
Following a thrilling climax to the first semi-final, Palace and Watford - both badly out of form in the Premier League - had much to live up to as they looking to join United in the final on 21 May. Both sides were looking to reach just the second domestic cup final in their history, with the pair also waiting for their first ever FA Cup success.
Pardew, who played for the Eagles on their last final appearance in 1990, named a full-strength side, making seven changes from the defeat to United in mid-week. Wayne Hennessey was restored in goal while Bolasie, Zaha and Wickham led the attack.
Opposite number Quique Sanchez Flores resisted the temptation to recall Heurelho Gomes after he saved two penalties against West Bromwich Albion, preferring to retain Pantilimon who had been an ever-present in the competition since his January move from Sunderland. Since their only final appearance in defeat to Everton in 1984, the Hornets had endure contrasting fortunes at Wembley; winning the Division One play-off final in 1999 before losing at the same stage to Palace in 2013.
And a repeat of that result looked on the cards from the outset as Palace took the lead inside six minutes. Damien Delaney's flicked header from Yohan Cabaye's corner looped towards the back post - catching out out Pantilimon - and allowed Bolasie to nod home his sixth goal of the season beyond the despairing dive leap from the Romanian 'keeper.
The response from Watford, who had not come from behind to win this season, was immediate and Allan Nyom's teasing cross caused havoc saw Joel Ward inadvertently shepherd the ball inches wide of his own goal. Palace continued to test Pantilimon however and the former Manchester City stopper nervously punched clear Cabaye's cross as they threatened a second.
Watford lost influential midfielder Etienne Capoue to a nasty-looking knee injury and then escaped conceding a penalty as Ake handled Bolasie's cross. The change however only worked to disrupt Flores' side who were finding the midfield tandem of Cabaye and Mile Jedinak difficult to breach as the game reached the half-way point.
The newly-promoted Watford escaped being reduced to 10-men when Miguel Britos felled Wickham and Palace almost doubled their lead when Pantilimon kept out Bolasie's drive with his legs. It was a missed chance which Palace would live to regret as Deeney nodded home just his second goal since February from point blank range after Watson's corner.
But the score was level for just seven minutes as Palace re-took the lead from the game's third headed goal. Papa Souare whipped in a cross from the left and Wickham beat Ake and directed the ball expertly into the corner.
Pardew's side continued to ride their luck in the eyes as referee Craig Pawson as Dann avoided being shown a second yellow card after a high challenge on Odion Ighalo. It was Ighalo who had Watford's best chance to force extra time but he failed to hit the target on the run to allow Palace to book their place in the 21 May final - a game which gives Pardew the opportunity to better his appearance as a player from 1990.