The Red Devils duo have struggled to convince in Jose Mourinho’s first-team over the past 18 months.
Mourinho used Martial sparingly throughout the 2016-17 season despite the France forward impressing under Louis van Gaal.
The Red Devils star has enjoyed more game time in Mourinho’s second season in charge but speculation persists surrounding Martial.
Pogba has been underwhelming in a midfield role alongside Nemanja Matic in recent months to prompt criticism of the record signing.
Manchester United manager Jose Mourinho has dropped Pogba in recent weeks, notably for both legs of their 2-1 loss to Sevilla.
Former Arsenal star Nicholas believes Martial and Pogba have allowed their performance levels to drop in recent months.
“A lot of the blame goes to Mourinho, but to the players as well,” Nicholas told Sky Sports.
“Pogba has switched off, Anthony Martial has let his level drop after being moved to the right and the defence has been all over the place because they’re not following orders.”
Manchester United finished in sixth place in the Premier League table last term under Mourinho.
The Red Devils won the Europa League and the League Cup in the Portuguese coach’s first season in charge at Old Trafford.
The 20-time English champions signed Chile international Alexis Sanchez in the January transfer window.
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