CARLTON co-captain Sam Docherty remains on course to face Richmond in the opening round of the 2020 season after receiving treatment in the United States.

The 26-year-old hasn't played for the Blues since 2017 due to back-to-back anterior cruciate ligament (ACL) tears, but has been receiving treatment from renowned reconditioning specialist Bill Knowles in Philadelphia as he targets a return to full training in mid-January.

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"I shot off to Philadelphia last week for a week with one of the physios from the club," Docherty told RSN.

"It was very good, very enjoyable, and I got a lot out of it to be honest."

The backline leader has had two reconstructions to his left knee, but is optimistic about his movements.

"I'm definitely leaner than I was last year, and less kilograms makes it easier to run. I'm a lot more confident in the movements that I'm doing."

Depsite his progress, Docherty won't be rushed back into full training.

"We're trying to take it as risk free as we possibly can," he reveals.

"I probably won't train fully until mid-January, but I'll be in and out of certain things from day one. We're taking as much risk out as we can before I need to put my body and knee at risk before playing practice games and getting ready for the season."

A return for Carlton's round one fixture against Richmond on Thursday 19 March at the MCG is still Docherty's aim, with the defender also hoping to participate in the 2020 pre-season in late February.

"My aim has always been round one and that's been the way we've set my program up, to give me the best opportunity to be ready to go and to perform, and (to have) my knee feeling as good as it possibly can for Richmond in round one."