The Lions have featured in the past three Super Rugby deciders but it was the Brumbies who looked like title contenders on Saturday night after taking their chances in the eight-try contest.
The Brumbies’ third win from eight games keeps them within touching distance in the Australian conference, but still seven points behind the leading Melbourne Rebels.
“It was a good performance with some really good passages. We managed to play with speed and tempo and that was our plan,” McKellar said.
“Tonight we took a few more opportunities when they presented instead of [identifying them] at review on Monday , so we’re pleased but we have plenty to work on.
“We can’t change what’s happened (with earlier results), we’ve just got to build momentum and take confidence and belief off the back of tonight.
“We have to do it again next week.”
Wallabies star David Pocock was a late scratching but the ACT men muscled up without him against a physical Lions forward pack in front of 7541 fans.
Brumbies livewire fullback Tom Banks returned to form with a stellar performance, while former NRL player Tom Wright overcame an early yellow card to score in his first start.
Wright was sin-binned for a tip-tackle after four minutes and the Lions made them pay when Springboks flyhalf Elton Jantjies switched play nicely and put Aphiwe Dyantyi into the corner for the opening try.
The Brumbies wasted several opportunities in a frustrating opening 20 minutes before Banks burst through a gap and Lachy McCaffrey finished the job to score from close range.
McCaffrey threw an audacious cut-out pass to one of the fastest men in Super Rugby, Toni Pulu, who raced 25 metres down the sideline to score on 26 minutes.
The Lions looked set to pinch the lead back before the Brumbies went 80 metres for Tevita Kuridrani to score and lead 19-8 lead at the break.
The Lions came storming back out of the blocks and Janjties swooped on a loose ball to score and make it 19-15 after 45 minutes.
Banks responded with a nice jink back inside to score and stretch the lead on 54 minutes before Wright dummied his way through for another moments later.
The seesawing contest continued when Sylvian Mahuza crossed but the Brumbies held their nerve for the final 10 minutes.
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