The Hornets have lost back-to-back games to fall out of the play-off places while the Blades have picked up just one point from three games since Christmas to fall off the pace in the promotion race.
Watford are unbeaten in each of their past four home league games against Sheffield United (W3 D1), keeping a clean sheet in each of those matches since losing 2-0 in January 2009.
Following a 1-0 win at Bramall Lane in September, Sheffield United are aiming to complete a league double over Watford for the first time since 2008-09 under Kevin Blackwell.
Watford were unbeaten in 15 straight home league games prior to losing to Cardiff in their final match of 2024 (W10 D5) - the Hornets last lost two in a row at Vicarage Road in the Championship in February.
Sheffield United are unbeaten in their past 13 Championship matches played on a Saturday (W9 D4), since a 1-0 loss at home to Luton in March 2023.
Sheffield United manager Chris Wilder has never won away to former side Watford in the league, drawing 0-0 with the Blades in the Premier League in October 2019 before losing 2-1 with Middlesbrough in the Championship in August 2022.