The Red Devils have made an impressive start to life under the Portuguese coach after the 20-time English champions recorded back-to-back Premier League victories.
United eased to a 2-0 win against Southampton at Old Trafford on Friday night thanks to Zlatan Ibrahimovic’s goals either side of half-time.
Mourinho’s side have scored five goals and conceded just once as the new United manager continues to transform the Red Devils into title contenders.
However, former Liverpool and Tottenham Hotspur midfielder Redknapp believes Mourinho could see a problem develop at defensive midfielder in the coming months.
“He is playing it low key which is something he doesn’t normally do. It something that suits him now. He respects the history of the club,” Redknapp told Sky Sports following United’s 2-0 win.
“There are still one or two things he needs to tinker with – and he will do in time. The defensive midfield position could become a problem. When I look at Jose’s team in the past.
“He had Makelele at Chelsea and Cambiasso at Inter – players who could always play in front of the back. He brought on Chris Smalling to make sure they sured it up and made them difficult to beat. That’s where a Carrick or Schneiderlin might come in.
“I’m still not sure Marouane Fellaini is the answer in the defensive midfield position.”
The Red Devils are currently at the top of the Premier League table ahead of Liverpool and Chelsea after two rounds of games.
The four-time European champions will make the trip to Mike Phelan’s promoted side Hull City in their next Premier League game at KC Stadium next Sunday afternoon.
United signed Eric Bailly, Ibrahimovic, Henrikh Mkhitaryan and Pogba in the summer transfer window.
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