Antonio Rudiger has urged Chelsea to hold onto his team-mate Callum Hudson-Odoi.
Hudson-Odoi has handed in a transfer request at Chelsea following a £35m bid from Bayern Munich, Sky Sports News understands.
Hudson, who has a contract until 2020, started and scored for Chelsea in Sunday's 3-0 FA Cup fourth-round win over Sheffield Wednesday.
Some Blues fans chanted "we want you to stay" after Hudson-Odoi's second goal for the club and Rudiger feels the same way.
The Germany international said: "What I can say is clear, Chelsea have to make him stay. It will be a pity if this young talent leaves us.
"Chelsea need to give him a new contract."
Rudiger, who joined Chelsea from Roma in July 2017 and began his career at Stuttgart, admitted earlier in January that Hudson-Odoi had asked him about life in the Bundesliga.
"He just asked me about normal things. At the end of the day, he decides about his future," Rudiger said. "He's a quality player. You can see how he dribbles, how he goes one against one, he can be good for us."
Hudson-Odoi admitted after Sunday's game he does not know if he will play for Chelsea again.