Injured Del Potro to miss Australian Open

Argentine Juan Martin del Potro says unfortunately he hasn't yet recovered from his knee injury in October and will miss the Australian Open in January.

Argentina's Juan Martin Del Potro says he's not ready to make his return at the Australian Open. (AAP)

Argentine ace Juan Martin Del Potro will miss next month's Australian Open.

The world No.5 is still recovering from a knee injury suffered in Shanghai in October.

"I hope you have a great 2019. Recovery is going great and I will tell you later where I will be making my comeback," he wrote on Twitter on Monday.

"Unfortunately it won't happen in Australia, I'll miss you @AustralianOpen, but I'm happy with my progress."

Del Potro, 30, had a largely successful 2018, winning at Indian Wells and reaching the US Open final.

In the Australian Open the Argentine has never made it past the quarter-finals stage, where he was knocked out in 2009 and 2012.