He wasn't at his best against Watford, but can't really blame him as he and the other players were obviously tired after playing 3 games in 6 days last week, so Watford's pressure, energy, aggression and physicality were too much to handle. That's why winning the game was was important, especially when you consider the losses of our rivals.
He also makes some very good points in his interview, it's not the usual generic rubbish that the other players tend to say after poor performances. Watford played without any pressure whatsoever and they were pretty close to going home with the 3 points had Ighalo scored some of his chances.