The Brumbies are licking their wounds from a costly Super Rugby season-opening defeat to the Melbourne Rebels.
Wallabies star David Pocock saw just five minutes of action at GIO Stadium on Friday night after copping an accidental elbow from Rebels skipper Dane Haylett-Petty.
Brumbies coach Dan McKellar says there are no guarantees Pocock will line-up against the Chiefs next Saturday night after he failed a concussion test.
Pocock endured an interrupted off-season, picking up neck and calf issues.
"He's obviously had a concussion on the (Wallabies') Spring tour as well so we'll just do what's in the best interest of Dave," McKellar said.
The Brumbies sorely missed Pocock as they went down 34-27 in the nine-try affair.
Haylett-Petty said seeing the John Eales medallist head to the bench was a big moment in the match.
"It was probably the highlight of my night taking 'Poey' out," Haylett-Petty said.
"I'm glad he's all right, but it's nice not having to play against him.
"Obviously he's so big for them, he leads them around."
Former Chiefs winger Toni Pulu had a nightmare debut in Brumbies colours, suffering a suspected fractured cheekbone.
McKellar fears the Wallabies prospect could be sidelined for an extended period.
"He's been such a great addition to the club, he's really popular amongst the group and brings a lot of experience and knowledge to our outside backs," McKellar said.
Fellow winger Henry Speight also pulled up sore with a hip complaint.
