Roy Keane insisted Paul Pogba is not at the centre of Manchester United's problems as he criticised Romelu Lukaku and new signing Alexis Sanchez.
Pogba was named among the substitutes before he replaced injured team-mate Ander Herrera after 17 minutes in United's 0-0 draw at Sevilla in the first leg of their Champions League last-16 clash on Wednesday.
The France international has dominated headlines amid a reported feud with manager Jose Mourinho, having been substituted in Premier League defeats to Tottenham and Newcastle United.
But former United captain Keane defended Pogba, though he demanded more from the 24-year-old midfielder, striker Lukaku and ex-Arsenal forward Sanchez, who was withdrawn 15 minutes from the end at Ramon Sanchez Pizjuan.
"Pogba is a really good player. He's under lots of pressure at the moment. There's lots of speculation about him," Keane told ITV . "He was left out but you'd still have Pogba in your starting XI.
"I look at Pogba off the field. He seems to have a big personality, whether it be social media, the cars he drives, his haircut. He needs to bring that onto the football pitch.
"Man Utd's problems are not just with Pogba. Lukaku's got to do better. Sanchez – I know he's new to the club – he's got to do better.
"They obviously need to reinvest in some defenders. You can't keep pointing the finger at Pogba but of course the lad has got to do better."
Keane continued: "You're talking about Man United, one of the greatest clubs on the planet. They still need to do better. And certain players need to up their game.
"Lukaku, for example – get hold of the ball. Whatever about putting the ball in the back of the net, get hold of it.
"And if you want to become one of the great strikers of Man United and you get the chance, like he did tonight, you've got to score in these tight games."
United – second in the Premier League – welcome reigning champions and fourth-placed Chelsea to Old Trafford on Sunday.