Alex Chamberlain's side secured all three points at Stevenage Borough's Broadhall Way ground courtesy of a Douglas Rinaldi goal five minutes before half time.
Spurs Res: Forecast, Ifil, Mills (Martin 15), Archibald-Henville, Daniels, Mtandari (Hutchins 60), McKenna, Lee, O'Hara, Hallfredsson; Barcham. Subs not used: Townsend, Burch, Smith.
Watford Res: Loach; Chambers, Doyley, Avinel, Powell (Parkes 60), Williamson, Rinaldi, Bangura (O'Toole 63), McNamee, Kabba (Campana 72), Hoskins. Subs not used: Beasant, Clarke.