Middleweight champion Robert Whittaker out until at least 2019

Whittaker says he 'definitely' won't be ready to fight until 2019 (0:50)

UFC middleweight champion Robert Whittaker talks about rehabbing his broken hand, saying February 2019 as an ideal date to be ready to fight. (0:50)

UFC middleweight champion Robert Whittaker told ESPN's Ariel Helwani on Monday that he won't be able to defend his belt until at least 2019. Whittaker said his ideal return would be in February because of injuries he suffered in his most recent fight, a split-decision win against Yoel Romero in June.

Whittaker (20-4) has won nine consecutive fights. He broke his right hand in the first round of that bout against Romero but continued to fight for the remaining four rounds. He told Helwani he also had ligament damage on his left hand, "but obviously the attention was drawn to the broken hand."

The Australian fighter had surgery this past month and will take the remainder of the year to recover.

"I haven't even started the rehab process yet," Whittaker said. "Just more letting it heal first before I can implement that. They put a plate and some screws in (on the right hand). Realistically I'm looking at February next year."

ESPN reported earlier this month that Whittaker and top middleweight contender Kelvin Gastelum expect to compete for the belt, but no date has been set. Both will also be coaches on the final season of "The Ultimate Fighter" reality series.

Gastelum (15-3, 1 NC) is coming off a split-decision win against Ronaldo "Jacare" Souza in May. He has won two in a row.

Whittaker does not anticipate any lingering issues for his next title defense.

"I'm not worried that it'll have any effect on my performance," he says. "I haven't even reached the peak of my potential. This hard fight is going to mold me and shape me as to how I approach fights from here on. I think everyone has to have their mettle tested in a tough fight. That was one of them for me."