Marcos Alonso does not understand why Callum Hudson-Odoi would choose to leave Chelsea and the Premier League behind to join Bayern Munich.
Teenager Hudson-Odoi is the subject of heavy interest from Bayern, which is said to be ready to part with £35million to bring the winger to the Allianz Arena.
The 18-year-old has featured in just one Premier League encounter this season, coming on as a first-half substitute for Pedro during the 2-1 win at Watford on Boxing Day, before being replaced himself late on due to injury.
Head coach Maurizio Sarri and his assistant Gianfranco Zola have both implored Hudson-Odoi to stay put at Stamford Bridge, and left-back Alonso has followed suit.
"He is a good player, but he is very young," said Alonso. "He needs to have patience and to be hungry and fight for a place in this team. That is all he needs to do, he has all the conditions to be a great player, now it is up to him to fight for a place here or try to find more minutes somewhere else.
"We are Chelsea, another great team, the Premier League is the most competitive league in the world, I don't know why someone would go to Bayern Munich."
Alonso played the full 90 minutes of Tuesday's 1-0 defeat to Tottenham in the first leg of the EFL Cup semi-final - a game decided by Harry Kane's penalty following VAR controversy.
The spot-kick was awarded after the technology ruled that Kane had been onside in the build-up, despite the linesman having stopped to put his flag up.
"Maybe we were unlucky because they only had one chance and that was thanks to the linesman, the VAR," Alonso said. "Watching it on video it looked offside and the linesman stopped so we all stopped.
"The referee told me they have explained it to us already but maybe they haven't explained it to the linesman because he stopped and if there is any doubt that it is offside he has to continue running. The guy stopped, if we have to wait for VAR I think he has to continue, but he stopped in the middle of the park. So it is a bit confusing when he stopped to put the flag up and then we have to keep running and it changes because maybe Kepa [Arrizabalaga] could have got to the ball quicker or a defender could have run back but we stopped.
"It created a lot of confusion, I don't know what they have to do, but they have to explain it properly to the linesmen and referee to us, because if the guy stopped then I don't know why play kept going."