Attack coach Scott Wisemantel has left his role with England, leaving boss Eddie Jones with another position to fill before the Six Nations.
The 49-year-old's contract with the Rugby Football Union ended after England's defeat by South Africa in the Rugby World Cup final this month.
Scrum expert Neal Hatley has already left to join Premiership side Bath.
Forwards coach Steve Borthwick is expected to join Leicester's coaching staff in the coming months.
However, the RFU is confident former England captain Borthwick will remain in position for at least the Six Nations, with Jones' side starting their campaign against France in Paris on 2 February.
Wisemantel joined the England coaching team in the summer of 2018 and is credited with sharpening the side's attacking play over the past 18 months.
However, the Australian has been courted by Rugby Australia and is tipped to join new coach Dave Rennie's backroom team.
"Scott's contract finished at the end of the Rugby World Cup and we had some discussions but he has decided to move on," Jones said of his compatriot.
"Whatever role he takes on next I know he will do an outstanding job because he was fantastic for us. We will miss him but we wish him all the best and his family."
Jones, along with his number two John Mitchell, is contracted until the summer of 2021.