Malky Mackay believes Darius Henderson should have been shown a straight red card for the challenge which has left Lee Hodson with a suspected broken ankle.

The former Hornets striker, who was making his first appearance of the season for Sheffield United this afternoon following a prolonged injury lay-off, had already been booked for a challenge on John Eustace went he went in very late on the full-back, who was stretchered off with his right leg in a brace and wearing an oxygen mask.

Asked his view of the incident following Watford’s 3-0 victory, Mackay said: “We’ve got a boy lying in hospital with a suspected broken ankle right now and I think his second booking was a straight red for me.”

The Blades were reduced to nine men before half-time when another Vicarage Road old boy, Lee Williamson, was shown a straight red card for a late challenge on Lloyd Doyley and the Hornets boss said: “The referee was ten yards away and standing and watching the whole thing. I think what he’s probably given it for is reckless endangerment where the player’s not in control of his body going into an action ie a tackle or a header, and I think Lloyd Doyley could have come out of that with a broken nose and thankfully he didn’t. I think the referee’s thought about that long and hard before he actually did it.”

However, Micky Adams felt “there’s a case for both players to feel a little bit harshly treated”.

The Blades boss was particularly aggrieved by Williamson’s dismissal and said: “If they’re going to send players off for that it’s ridiculous. It’s a booking. Straight red? Violent conduct? I’m not sure about that.”

Asked about Henderson’s earlier sending off, Adams responded: “I think the referee left himself nowhere to go after the first booking. I don’t think it was a yellow card offence. I think Darius’ reputation, particularly here, has gone before him.

“And then the second one, I will defend Darius here and I’m upset that one of their players has been stretchered off – I hope he’s OK, I hope he’s well and not seriously injured – but quite clearly Darius is watching the ball and as far as he’s concerned, after the header, he thinks it’s a goal-scoring opportunity and I think he’s right. I don’t see a centre forward pulling out of that challenge at all, so I don’t think there’s any intent on his part to cause the boy and harm.”