A hamstring injury suffered during the previous week’s shock loss at Catalans Dragons restricted Kelly’s involvement to a pre-match lap of honour celebrating the deal which will keep him at Hull until the end of 2020.
Jordan Abdull, who would have deputised, sustained a broken leg during the game in France so Jake Connor switched from centre into the play-making role and produced a man-of-the-match performance. His drop-off pass created the opening try and he booted four goals from as many attempts.
It was a strong response by Hull to the setback seven days earlier and particularly impressive considering they began the game with one specialist in the halves and ended with none.
A knee injury suffered by Marc Sneyd early in the second half was a major concern for the Black and Whites, who climbed above Castleford into fourth place in the Betfred Super League table.
Hull did not have it all their own way in the first half, but two tries in three minutes around the half-hour mark established a dominance they never really looked like giving up, despite a spirited effort by the visitors after the interval.
Sika Manu took advantage of Connor’s creativity to edge the hosts ahead after 13 minutes, but Tigers replied in spectacular style almost immediately.
Jamie Ellis’s high kick was taken brilliantly by Michael Shenton, who lobbed a pass infield to send Paul McShane over and Ellis’s conversion cancelled out Sneyd’s similar effort for Hull.
There was a suspicion of obstruction when Jamie Shaul weaved over for an unconverted try to restore Hull’s lead three minutes later, before Manu added his second touchdown on 28 minutes.
Sneyd’s kick to the corner was dropped by Calum Turner, the youngster who had just come on for his Castleford debut, and Manu was gifted a walk-in.
Sneyd added the extras and three minutes later the scrum-half inflicted more pain on his former club. This time his kick was knocked back by Connor to Josh Griffin and he sent Bureta Faraimo across the line.
Facing a 14-point deficit, injury-hit Tigers looked on the verge of a heavy defeat, but they dug in and had the better of all but the final stages of the second period.
That will give them something to build on going into Saturday’s Challenge Cup tie against Super League leaders St Helens, but injuries to key players is a mounting concern.
Castleford were without ‘Man of Steel’ Luke Gale due to a fractured kneecap suffered in the previous game against Wakefield Trinity.
He joined full-back/stand-off Ben Roberts on the sidelines, along with Greg Eden, Jake Webster, Nathan Massey and James Clare.
Tigers fielded forwards Joe Wardle and Alex Foster in the centres and Shenton switched to the left-wing. When Jake Trueman sustained damage to his jaw midway through the first half, Shenton moved further out of position to full-back.
Castleford also lost prop Grant Millington to a head knock and were down to two available players on the bench for more than half of the game.
Wardle was penalised for interference on Connor at the start of the second half and the stand-off got up to take the two points with a long-range kick, but Turner gave Castleford hope on 50 minutes, profiting from an error by Shaul, moments after Manu had been held up over the line by McShane.
Ellis converted and Turner was denied a second try by a touch judge’s flag, for a foot in touch, with 17 minutes left. Griffin’s pass sent Faraimo over to make the game safe soon afterwards, Connor converting, adding a penalty and booting the extras to Griffin’s late touchdown from his winger’s break.
Hull FC: Shaul, Faraimo, Griffin, Tuimavave, Talanoa, Connor, Sneyd, Taylor, Houghton, Bowden, Manu, Minichiello, Handley. Substitutes: Green, Paea, Matongo, Westerman.
Castleford Tigers: Trueman, Minikin, Foster, Wardle, Shenton, Ellis, McShane, Watts, Milner, Sene-Lefao, Holmes, McMeeken, Cook. Substitutes: Moors, Millington, Springer, Turner.
Referee: G Hewer (Whitehaven).