Watford beat Stevenage 2-0 in Thursday's friendly at the Lamex Stadium courtesy of second-half goals from Etienne Capoue and Jerome Sinclair.
The Frenchman opened the scoring shortly after the interval when he blasted an effort into the top corner from outside the area.
Sinclair - who came off the bench to replace Odion Ighalo at the hour mark - put the match to bed late on with a header at the far post.
Watford could easily have won by a bigger margin, but Ighalo and fellow striker Troy Deeney were unfortunate not to find the net.
Ighalo had an attempt cleared off the line early on after latching on to Steven Berghuis' clever throughball, while the Nigerian forward saw another shot cleared by Fraser Franks moments before it would have gone in. The striker then hit the crossbar with a powerful shot from close range at the hour mark as he ended the game goalless.
Deeney, meanwhile, was denied by the woodwork as well, seeing his shot halfway through the second half bounce against the upright after some good work from Sinclair.