Watford could be promoted to the Premier League if they win against Leeds and Hull City slip up at home to Cardiff City.
Tonge believes that Watford could be the team under pressure as they seek a second-placed finish, which may help Leeds to secure a result at Vicarage Road.
He told the club's official website: "It's going to be a tough game for us with their situation.
"They will be nervous, I don't think they would be human if they weren't. Obviously if Hull win they will be promoted, but Watford won't want Hull to get beat and not have taken advantage of that.
"They will be up for the game I'm sure, but when there is so much riding on it I'm sure they will be nervous so hopefully we can take advantage of that."
Leeds have won just three times away from home in the Championship this season.