The 19-year-old conceded a first half penalty when the United striker handled inside David De Gea’s penalty area.
And CSKA striker Seydou Doumbia broke the deadlock after David De Gea had initially saved Roman Eremenko’s spot-kick.
But Martial made amends in the second half with a brilliant 65th-minute header to secure a point for the visitors in Moscow.
And Fellaini, who replaced Bastian Schweinsteiger at half-time in the Champions League clash, sent Martial a message on Instagram after his vital equaliser.
Fellaini wrote on the Instagram page: “Tough game but important point … Good goal @martial_9”
The Red Devils are in second place in Group B and two points behind Bundesliga Wolfsburg ahead of their return game against CSKA at Old Trafford.
Martial has scored five times in nine games in all competitions for the 20-time English champions after his £36m move from Ligue 1 outfit Monaco in the summer transfer window.
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