Luiz, 25, and Cahill, 26, have both been signed by the club over the last season-and-a-half and with John Terry reaching the latter stages of his career the duo could be exposed to more playing time.
And Duberry believes that Blues boss Roberto Di Matteo will want to pair the two players up as often as he can this season to ensure they will blossom into the club’s long term partnership in defence.
He told the Weekend Sports Breakfast: “JT is getting older and getting injury-prone, so I think they want to get Cahill and Luiz together for the long term but I still think both of them don’t really work well as a duo, and JT is good because of his experience.
“It’s something that I think going forward they want them to gel, and gel quickly. Not that I’m saying they want JT out but for long term plans, I think that’s why they bought them, they’ve got these two to form a partnership for many years.”