Watford remain rooted to the foot of the table and four points adrift of safety.

"We needed to win this match," said Flores. "They used their tools, and we used our tools, but we created the best opportunities and that is very clear.

"With these attempts, if the players felt more security, they would make the good decisions with the last pass, and the last shot.

"We know that if we don't change, we are going to suffer, so the clean sheet is a good base to build from.

"It is a long time since we had one so it is necessary. You can take confidence and grow from that. We are not exactly the team we want, but we are on the road to finding it."

The Blades, who have now taken their points tally to nine from their opening eight matches back in the big time, had greater possession and control of the 90 minutes. But Watford enjoyed a hat-trick of chances to claim their first three points of the campaign.

Andre Gray missed an open goal in the opening period before Blades' goalkeeper Dean Henderson atoned for his error in last weekend's defeat against Liverpool with two fine saves – first denying Danny Welbeck before producing a fingertip save from Craig Dawson's header in stoppage time.

Henderson, on loan from Manchester United, was the villain a week ago after he allowed Georginio Wijnaldum's volley to slip through his legs and afford Liverpool a slender 1-0 win.

But the young stopper bounced back by rushing out to prevent Welbeck from scoring his first Premier League goal since the opening day of last season. He then produced a fine diving save when Dawson looked set to convert Gerard Deulofeu's late free-kick.

Chris Wilder was critical of the 22-year-old following last weekend's clanger, but after saving his side a point, the Blades boss heaped praise on his goalkeeper.

"He has been outstanding," said Wilder. "It stung him last week, but he came roaring back today.

"These things happen in football and in life and it is how you react and overcome the next hurdle. It is no surprise what he has done. He has been neat and tidy in his work and is a really good goalkeeper."