He was injured following a challenge by Spurs defender Danny Rose, and it was confirmed by the Red Devils' Twitter account:
After the game, United manager Jose Mourinho suggested the midfielder will likely miss the team's next match against Crystal Palace, although the injury is not a serious one:
Mkhitaryan, starting just his third Premier League game of the season for United, had earlier given his team the lead with a powerful finish.
The former Borussia Dortmund man has had a testing start to life at Old Trafford following a big-money move this summer, although he has showcased his quality with some tremendous displays recently.
While United are flush in attacking areas, Mkhitaryan is a unique player. The 27-year-old is versatile in where he plays on the pitch.
Mourinho values players who work hard off the ball, too, which is another box Mkhitaryan ticks. Ahead of what is a congested festive period, that blend of intricacy and industry would be missed.
As for potential replacements, Juan Mata is the player who occupied an attacking berth earlier in the campaign when Mkhitaryan was settling into the Premier League and is the most similar footballer in style to the Armenian in the current squad. Players like Jesse Lingard and Marcus Rashford can provide penetration from the flanks if needed.
Nevertheless, having suffered a knock earlier in the campaign, United fans will be disappointed to see Mkhitaryan in the wars again. After some sparkling recent form, they’ll want the midfielder back on the field again as soon as possible.