The veteran left-back penned an extension on his contract last month and his understudy Bertrand has welcomed the move despite the fact it likely continues to keep him out of the Blues first team.
"I have said from the start that he deserves another contract," Bertrand said. "We have a good relationship. I'm always learning and there is no one better to learn from.
"He has given me plenty of advice over the years. The best advice is not so much what he has given me verbally but just watching him every day and the way he goes about his business.
"It (their relationship) reflects in our performances when we play together and I am in front of him at left midfield. It is probably the natural progression to share the left-back role, but I don't pick the team.
"I just get my head down, train well and hopefully that time will come."