Hull's move for Success reportedly broke down earlier this week and Success has now been seen leaving the Watford training ground, on his way to sign a loan deal for either Brighton or Sheffield Wednesday.
The Hornets' expensive flop managed just one goal in 17 Premier League games last season. However, before that Success has broken into the Granada first team playing 30 times, scoring six goals and providing two assists in La Liga's 2015/16 season.
Now the 21-year-old is set for a move away from Vicarage Road in order to find his form again.
Nevertheless Watford boss, Marko Silva, insisted earlier this month that the youngster, who has one Nigerian international cap to his name, still has a future with the Hornets:
"This situation: He's a young boy and boy who needs to adapt to this football and to our ideas as well," claimed Silva.
"We tried to put that to him as soon as possible because he's one player we believe in as a project - as a Watford project."
Watford are set to axe their misfits Jerome Sinclair and Isaac Success to fund a move for Islam Slimani— Bolarinwa Olajide (@iambolar) August 29, 2017
Sheffield Wednesday seems like the more likely destination for the Nigerian given that they will be able to offer him more game time, given that Brighton already have Anthony Knockaert and new signing Jose Izquierdo in wide areas.