Van Gaal has fallen out with 25-year-old Argentine Rojo following his failure to meet up with his Man United team-mates on their pre-season tour and AS Monaco are known to be keen on the versatile defender.
Martins Indi was a regular in the Dutch national team set-up under van Gaal and could well be ready to quit FC Porto to make the move to Old Trafford.
A January move for the 23-year-old could well be likely given that first-choice left-back Luke Shaw looks set to sit out the entire season following the double leg fracture he suffered during Man United’s Champions League defeat to PSV Eindhoven.
A move for Indi could cost Man United a big fee given the former Feyenoord man is tied down to a long-term contract that runs until 2018.
The presence of national team colleagues Daley Blind amd Memphis Depay at Old Trafford could act as further motivation for Indi.