Even City's assistant manager Eric Black, standing in for the absent Gary McAllister, admitted: "It was a striker's goal. It certainly was an exceptional shot."
City had enjoyed the better of the first half but the nearest they had come to scoring was three minutes from the interval when Stephen Warnock produced a long-range effort which Watford's man of the match, Lenny Pidgeley, did well to turn round the post.
Watford gradually asserted themselves after the interval and poured forward but Pegguy Arphexad did not really have a save to make until late in the game.
Then he parried a shot from Paulo Vernazza and the defence happily conceded a corner as Watford's leading scorer Scott Fitzgerald looked set to sweep the ball home.
City's relief was only temporary because from Neal Ardley's flag kick Sean Dyche headed firmly for goal. Arphexad parried the effort again and Fitzgerald was on hand to score his fifth of the season.
"I thought that would be enough to win it. I couldn't see City coming back," said Watford boss Ray Lewington after the match.
"The trouble is we became a little nervous and hesitant but credit to Coventry who probably thought they deserved the point and were certainly the better side in the first half.
"They did equalise with a quality strike and on such occasions you just have to hold your hands up."
Watford were under pressure in the last few minutes and twice cleared their lines but on the second occasion Warnock gathered the ball and put over a cross towards Staunton who turned to fire the ball straight into the top corner.
The Hornets have now gone five games without defeat.