With second-placed Ipswich drawing at West Brom, Kim Hellberg’s side have moved to within a point of the top-two positions with one game to play, although Ipswich still have a game in hand as the promotion battle heads towards its climax.

Boro’s 5-1 victory was their joint-biggest win of the season and came courtesy of doubles from Morgan Whittaker and Tommy Conway plus a goal from David Strelec.

Watford’s goal came at the start of the second half from James Abankwah, but while the visitors were a match for their opponents for most of the first period, they were comprehensively outplayed after the break.

Boro’s sixth-minute opener was a spectacular effort, with Whittaker firing a 30-yard free-kick over the Watford wall and into the top left-hand corner.

Watford came close to claiming an equaliser when Luca Kjerrumgaard fired just wide after Edo Kayembe crossed from the left, and struck the woodwork towards the end of the first half when Boro goalkeeper Sol Brynn touched Kjerrumgaard’s low strike on to the post.

Boro’s attacking lacked much of its usual cohesion but, just as Watford looked to be getting on top, the home side doubled their lead in first-half stoppage time.

Alex Gilbert’s pass released Whittaker into the right of the box, and when the winger slid over a low cross from the right, Strelec bundled home from close range.

Watford did not really deserve to be two goals behind at the break, and the visitors halved their deficit within three minutes of the restart.

Middlesbrough’s defence failed to adequately deal with a corner, and when the ball was returned to the 18-yard box, Abankwah lifted a shot beyond Brynn.

However, 10 minutes later, Boro restored their two-goal lead as Whittaker claimed his second goal of the game. Matt Targett’s low cross was deflected into his path and, from an acute angle, Whittaker swept home a fine finish.

Boro missed their leading scorer badly when he was sidelined for five matches recently and Whittaker, who also smacked a long-range strike against the crossbar moments before he was substituted in the second half, now has 14 goals this season, cementing his place at the top of the Teessiders’ scoring charts.

Boro added a fourth goal from the spot with 15 minutes left, with Tommy Conway converting after Abankwah handled from Targett’s corner.

And Conway completed the scoring with his second goal in stoppage time, turning neatly in the box before firing home a low finish.