Rangnick was compelled to leave one area at the substitutes bench unfilled at Villa Park after Martial opted no longer to make the trip to Birmingham.
United's interim manager said the 26-12 months-old did not need to journey to Birmingham as he pushes to depart before the January switch window closes.
Martial, linked with a loan flow to Spanish club Sevilla, has no longer played for United for the reason that three-2 win over Arsenal on December 2 - the final game earlier than Rangnick officially took fee at Old Trafford.
"Yes, he failed to need to be within the squad," Rangnick informed newshounds.
"He could have been in the squad usually, but he didn't need to and that's the cause why he changed into now not journeying with us the day gone by."
Martial joined United in 2015 from Monaco however has struggled to hold down a everyday first-group place in current seasons.
He is below settlement at United until 2024, with the club keeping the choice of an additional 12 months.
