2. Ander Herrera keeping an eye on Marco Veratti:
United's defensive midfielder Nemanja Matic should spend the majority of the match inside his own half, as he would have to play his part in blocking the shots of Di Maria and helping the centre-backs. Therefore, Ander Herrera, their other holding midfielder, would have to keep an eyen on Marco Veratti, PSG's playmaking central midfielder.
Veratti would try to find Mbappe, Draxler or Di Maria with his incisive passes, and therefore, Herrera can not afford to allow him too much space and time in the midfield. Herrera's battle with Veratti would be key in deciding the fate of the match, as Paul Pogba is expected to play in a more attacking role.
Herrera has a very good passing range himself, and is capable of delivering vital through balls. However, he can not afford to go into attack very often, and would have to play his part in nullifying Veratti's passing game to an extent.