Back-rower Glenn had hoped to make his debut as Broncos skipper at this week's Nines after officially taking over the reins from Darius Boyd in the off-season.

And winger Coates was looking to push his case for a 2020 backline berth ahead of the season kick-off in WA after being included in a strong Broncos Nines squad.

However, Brisbane were forced to withdraw the duo and add Kotoni Staggs and teenager Brendan Piakura to their squad as they prepared to fly out to Perth on Wednesday after the duo experienced tightness in their legs.

"With the long flight to Western Australia a factor, they have been scratched from the squad," a Broncos statement said on Tuesday night.

It was a blow for caretaker coach Kurt Richards who takes over the Broncos reins from Anthony Seibold in Perth.

Before the injury news broke, Richards said he had hoped Brisbane would create some momentum in WA after their embarrassing 2019 NRL finals exit, copping a record 58-0 thrashing from Parramatta.

But it remains to be seen how the Broncos bounce back from the loss of the inspirational Glenn and speedster Coates in Perth.

"The boys have been working hard for 13 weeks so they are jumping out of their skins to play any format of the game," Richards said on Tuesday morning.

"We have put a strong side together but obviously we will be judged by our results.

"We want to be a group that competes really hard for each other.

"Two of the four teams (in a pool) will go through so we are going to have to start fast, and we have been preparing that way."

Australian Associated Press