The Red Devils made the trip to the English capital in search of a third successive Premier League win following victories over promoted clubs Newcastle United and Brighton Hove and Albion over the past fortnight.
Manchester United were leading 3-0 at half-time at Vicarage Road after Ashley Young scored twice in six minutes before Martial netted his sixth goal in 14 appearances in the Premier League in the 2017-18 season.
Watford captain Troy Deeney reduced the deficit from the penalty spot in the 77th minute before the Hornets made it 3-2 with five minutes to go before Jesse Lingard’s late goal restored Manchester United’s two-goal cushion.
Martial has netted eight goals and has made four assists in 19 games in all competitions to make a promising start to the season despite finding his first-team opportunities somewhat limited under Jose Mourinho.
The 21-year-old netted 17 times in all competitions in his first season at Old Trafford under Louis van Gaal following a £36m move from Ligue 1 side AS Monaco in the 2015 summer transfer window before Mourinho’s appointment in May 2016.
Former Manchester United midfielder Scholes believes Martial’s career could be about to take off at Old Trafford.
“It’s as good as I’ve seen him all season [against Watford on Tuesday night],” Scholes told BT Sport.
“Martial has been saying he thinks he’s a centre-forward, he showed he has the composure there. Hopefully this is the start of big things for him.”
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