The win gave Hull a Premier League lifeline as they moved level on points with West Ham with a game in hand.
Gianfranco Zola’s side only stayed out of the bottom three on goal difference after suffering a sixth consecutive defeat against Stoke City.
A West Ham source said: "Roy Hodgson admitted on TV that he rested players because he had an important Europa League match coming up. He admitted fielding a weakened team. From our point of view that is awful and we are going to put in a complaint."