Scott McTominay’s fourth-minute header was enough to give Manchester United an unconvincing victory in their FA Cup third-round tie against Watford on Saturday.
Wearing the captain’s armband for the first time in a much-changed side from Wednesday’s Carabao Cup semi-final defeat by Manchester City, McTominay found the net after rising to meet Alex Telles’ corner.
The hosts did have chances to increase their lead, but Juan Mata failed to find a finish to an excellent three-man move just before half-time, then Daniel James and substitute Marcus Rashford had shots saved after the break.
But none of those opportunities were better than that for Hornets defender Adam Masina, who saw his effort blocked by United keeper Dean Henderson not long after McTominay had struck.
Now under their fifth manager in two years, Xisco Munoz, Watford had other chances too – Joao Pedro’s header went straight to Henderson and Ken Sema was off target with his.
Mason Greenwood and Donny van de Beek did little to press their claims for a regular starting slot in manager Ole Gunnar Solskjaer’s side, while Jesse Lingard – making only his third appearance of the season and the subject of interest from a number of clubs in the January transfer window – showed glimpses of form but eventually faded.
United will go into the hat for Monday’s fourth and fifth-round draws, while Watford are left to focus on winning promotion back to the Premier League at the first attempt.
Given the increasing awareness of the effects of concussion, the decision of United’s medical staff to take no risks with defender Eric Bailly when he was caught in the head by Henderson’s knee as the keeper punched clear was a welcome one.
The Football Association had hoped to introduce concussion substitutes by now but it has not yet been able to as detailed protocols are yet to be received from Ifab, the world game’s rulemakers.
As Bailly was guided towards the tunnel in the last minute of the first half, Harry Maguire replaced him and helped United keep the clean sheet which ensured they reached the fourth round for the 34th time in their past 36 attempts.
Afterwards, United manager Ole Gunnar Solskjaer said: “I think it was his neck. I don’t think it was concussion so that is a positive. But we have got to do scans.”
Manchester United manager Solskjaer said: “Scott has got everything a leader has to have. I wanted to test him by making him captain and see how he would react.
“He delivered and he always does. He was brilliant today.
“We have always trusted our young men coming through and Scott is one who we believe has the Manchester United DNA in him and knows what it is to be a Manchester United player.”
McTominay on captaining the side: “When the manager told me it was a surreal moment. I’ve been here since I had just turned five, so that’s 18 or 19 years associated with the club and it is a huge honour.
“I love this club and it has been my whole life.”
United turn their attentions to a big week in the Premier League. Solskjaer’s side travel to Burnley on Tuesday (20:15 GMT) knowing victory will send them top of the table above Liverpool – who they then play at Anfield on Sunday (16:30 GMT).