Both players had been major concerns ahead of the trip to Wembley, but were part of the travelling party that boarded a train to London on Wednesday afternoon.
Lukaku has been sidelined with an ankle injury picked up in the victory over Arsenal at the end of last month, while Martial was a surprise absentee against Watford last time out.
Man Utd's travelling squad for FA Cup final
David de Gea, Sergio Romero, Joel Pereira, Matteo Darmian, Antonio Valencia, Eric Bailly, Victor Lindelof, Phil Jones, Chris Smalling, Marcos Rojo, Daley Blind, Luke Shaw, Ashley Young, Ander Herrera, Scott McTominay, Marouane Fellaini, Nemanja Matic, Paul Pogba, Juan Mata, Jesse Lingard, Alexis Sanchez, Romelu Lukaku, Anthony Martial, Marcus Rashford
Having returned to Belgium to receive treatment for the knock, Lukaku has now been passed fit and there is even a hope that he could start Saturdays contest.
Martial, meanwhile, only suffered a slight knee injury and missed the final training session before the clash against Watford, and there was always optimism that he would be available against Chelsea.
There were no other notable absentees from the group of players that boarded the train from Stockport Station, and the squad – and manager Jose Mourinho especially – looked in good spirits.
Interestingly, Michael Carrick, who will hang up his boots at the end of the season and join Mourinhos backroom staff, was not wearing the players green training tops and was instead in the coaches black attire.
United will train at Fulhams Motspur Park training ground over the next couple of days as they prepare for their FA Cup final showdown.
Mourinho is expected to speak to the press for the final time at Uniteds hotel on Friday afternoon, following the same routine as against Tottenham for the semi-final.
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