The Brumbies have returned to the top of the Australian Super Rugby conference after defeating the Lions 30-20 in Johannesburg.
But the win may have come at a cost with Wallabies star Matt Toomua re-injuring his ankle.
Toomua's injury was the only blemish in their bonus-point win over the much-improved Lions.
Returning at inside centre after five weeks on the sidelines, Toomua limped off after just 24 minutes with a recurrence of the same high-ankle injury.
The Wallabies playmaker will likely have scans on Monday when the squad return to Canberra, but team management were optimistic that Toomua - following a week's rest for the bye - will be fit to face the Bulls at home the following round.
Toomua's availability will be crucial over the final three rounds against the Bulls, Western Force and Crusaders, with the Waratahs set to leap the Brumbies on the table if they beat the Crusaders on Saturday night.
Brumbies coach Stephen Larkham was thrilled with the turnaround after a disappointing loss to the Stormers the week before in Cape Town.
Christian Leali'ifano opened the Brumbies' account with a 15th-minute penalty and a dominant period followed for the visitors.
Centre Tevita Kuridrani scored in the 18th minute after several phases of sustained pressure and Ita Vaea crashed over only a few minutes later after a Jesse Mogg counter-attack put Henry Speight into space down the right flank.
Leali'ifano then left the Lions shell-shocked, intercepting a pass on the Lions' 22 metre line and scoring under the posts to push the Brumbies' lead out to 22-6 after 27 minutes.
The Brumbies' four-try bonus point came in the 72nd minute after Mogg put winger Joe Tomane in the corner.
Mogg slotted a late penalty from 55 metres to seal the win, having earlier pushed two long-range kicks wide, including one from 62 metres.
Hard-working Lions backrower Jaco Kriel was rewarded with a second-half try, while fullback Andries Coetzee scored a late consolation try.