The 29-year-old believes United will feel his absence.
"Especially at home it's a big loss for them because it's a big pitch," said Konchesky. "He's a strong lad and he's quick, but they've got other players who can play there.
"That's why they are there or thereabouts every year. People can come straight into the team. It could be Nani or they could play Fletcher there."
Konchesky's opposite number on Sunday lunchtime will be Patrice Evra, a left-back he admires.
"I rate him really highly," Konchesky told liverpoolfc.tv. "He's one of the best left-backs in the Premier League and he settled in really quickly at Manchester United. He's one of their most consistent players and is probably one of the first names on the teamsheet."