Danny Mills has questioned whether Liam Cooper is good enough for the Premier League if Leeds United were to gain promotion.
The former England international, speaking exclusively to Football Insider correspondent Dylan Childs, insisted the Whites would need a different calibre of player for the Premier League.
Cooper has been a mainstay under Marcelo Bielsa making 30 appearances so far this campaign.
The 28-year-old became only the twelfth player to wear the armband 100 times for the Whites, joining club legends Gordon Strachan and Billy Bremner in achieving the feat.
When asked who he thought would struggle to make the jump to the Premier League if United were promoted, Mills told Football Insider: “Some players are better suited to the Championship and that is their level.
“Liam Cooper has been a magnificent servant and he is the captain of the club but – is he quite good enough for the Premier League? Sheffield United proved a lot of people wrong but I think they need to add a little bit of strength in that position.
“A lot of the decisions will all be about whether they get promoted or not. There will be a plan for if they are promoted and if they are not.
“They will have players in mind for the Championship and if they get to the Premier League but if they do they will need to add quality to the squad, nobody would disagree with that.”
With Ben White only on a season-long loan from Brighton and Gaetano Berardi’s contract up this June, Marcelo Bielsa will need to address his defence in the summer.
United are now six wins away from returning to the Premier League for the first time since 2004.
In other Leeds United news, Noel Whelan has told Football Insider which Elland Road player is “really special”.