The Frenchman has been in fine form this season despite United's struggles (he is their top scorer with nine goals) but caretaker boss Ole Gunnar Solskjaer has revealed that Martial has missed out due to feeling ill.
The Norwegian took charge of his first game on Saturday, leading his former side to a 5-1 win.
There was a time when full-backs pushed high and wide at Old Trafford was the norm but they are two of the positions to have suffered most in the post-Ferguson landscape.
United have managed to win just five of 12 matches at Old Trafford in all competitions so far in this disappointing campaign, with the pressure appearing to be too much for players at times. But some of the players let me down and let themselves down.
"We prepared right", Giggs later said after a 1-0 loss.
"They're the best fans in the world", he added.
That is as good as a manager could hope for, but wins are wins and the confidence of underperforming United players needed picking up off the floor.
However, they couldn't maintain the winning mentality as they surprisingly lost to Brighton 3-2 in the second match of the campaign.
"So why should we stop them?"
The two players offer different qualities so Ole would be wise to use them when he sees fit according to the occasion and opponent.
Man United have had great wingers in their history but ever since their Sir Alex Ferguson left, the time of wingers seems to have faded.
"We really wanted to press them, but we were not clinical enough and this is absolutely where we have to improve".
One game, one performance, is not going to paper over the cracks of what remains a United squad in need of much more than short term festive joy. I don't like that managers get sacked but especially if we play the teams soon after this happened, like (Southampton) as well.