Blackburn are back in the Championship play-off race after three successive victories but have only won one of their past five home games.
Watford are on a three-match losing streak which has cost them a possible top-six finish.
Blackburn lost this fixture 2-1 last season but have never lost consecutive home league games against Watford.
Watford are looking to complete their fourth league double over Blackburn, previously doing so in 1970-71, 1981-82 and 2020-21.
Blackburn have won their past three league games, as many as they had in their previous 15 (D2 L10).