Newcastle United were beaten 3-0 by Watford at St. James' Park this weekend.
Watford won 3-0 against Newcastle on Saturday, with Marco Silva’s side looking a class apart from the Magpies.
However, Gray has stated that he felt Watford didn’t play anywhere near their best in the contest.
The £18.5 million striker (Telegraph) said: "I think if anyone has seen us throughout the season, we have been a lot better.
"We got a bit complacent and a bit sloppy at times. I think I should have come off with the match ball. I have missed two good chances and should have done better.
"Like I said, I think everybody knows we can play better."
Gray’s comments must be of huge concern for Newcastle, as if Watford can dominate them in such fashion, without playing to their best, then it shows how far off the pace they currently are.
Watford have been the surprise package in the Premier League this season, and posses a great deal of quality, but Newcastle must be worried if they can get past them so easily.
Newcastle have generally competed well since earning promotion back to the top flight, but their form over recent weeks have been poor.
Newcastle have lost their last four matches to slip down to 14th place in the Premier League table.
And unless Rafael Benitez can spark an improvement in his side in the near future, they could be left looking nervously over their shoulders, with the relegation zone moving closer and closer.