Tom Cleverley, signed on loan by Watford onMonday from Manchester United, wrapped up a thrilling win for his new side last night.
The 20-year-old midfielder latched onto a Tommy Smith pass in added time to drill home and seal Watford's first victory of the season.
Smith, who could be sold to Reading this week, underlined his value to the team and the Royals may just have to pay a bit more if they are to secure his services.
Danny Graham had put Malky Mackay's side ahead just after the half hourmark with a header from six yards out, but Dexter Blackstock restored parity on the stroke of half-time following a Paul McKenna pass.
Defender Mike Williamson restored Watford's lead by poking home from close range after Smith's header had rebounded off the cross bar.
A relative avalanche of chances then emerged as Smith quickly extended the lead with a shot from outside the box.
Dele Adebola, a 75th-minute replacement for Blackstock, coolly rolled the ball past Scott Loach to set-up a tense finale.
But Cleverley ensured that Watford would leave with the three points, as Forest continue tolook for their first victory of the campaign.