Bertrand doesn't want to be seen to be telling the Blues how to run their business, yet he would prefer if their departures were postponed for a few more years.
He told the London Evening Standard: "The success the club has had with them in the team speaks for itself. On and off the pitch they are massive role models. They are fantastic people to be around and for someone like me to learn from them, it's a great opportunity.
"I want them to be around as long as possible. When you're friends with people, you never want them to move on. You look at the core of the team over the years, when the whole new Chelsea started, it was Petr Cech, JT, Lamps and Didier Drogba through the middle and three of them are still here."