After winning their first two games of the season it has been all downhill for the Cheetahs, and they had no answer against a Brumbies side who go top in the Australian conference with the win.
Christian Lealiifano scored a try, kicked two conversions and scored two penalties while Blake Enever also crossed for the hosts. A sole penalty from Joe Pietersen was all the Cheetahs had to show for their efforts.
It took only three minutes for the Brumbies to score the first try, with Lealiifano bouncing off a weak tackle from Pietersen to go over the line.
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Scott Sio threatened to add another try just three minutes later but this time the Cheetahs stopped them - and they were back in touch when Pietersen nailed his penalty in the 16th minute.
But Lealiifano answered in kind four minutes later and he added another on the stroke of half-time to give the hosts a 13-3 advantage at the break.
Just as they did at the start, the Brumbies struck early in the second half as they won a line-out and drove over the line for Enever to score four minutes in.
Lealiifano kicked the conversion, but with the result pretty much settled the game soon became subdued.
The Cheetahs had the best of the final 10 minutes, but never really threatened to score, and must go back to the drawing board as they head to Perth next to face the Force.
The Chiefs rallied from 13-10 down early in the second half to defeat the Blues 23-16 at Waikato Stadium in Hamilton on Saturday.
The result extended the Chiefs' winning streak over the Blues to nine matches, and improved their season record to six wins in eight to keep them second in the New Zealand conference and also second in overall points behind competition leaders the Hurricanes.
For the bottom-of-the-table Blues, in contrast, it was a seventh straight Super 15 loss.
The game was a scrappy affair, the Chiefs suffering from a misfiring line-out and giving up a plethora of turnovers, while the Blues struggled to get out of their own half and paid heavily for a lack of discipline.
The hosts looked to be have everything under control after surging into a 10-0 lead in the first half-hour thanks to an 18th-minute penalty from Aaron Cruden, having missed his first two attempts, and a converted James Lowe try.
Dan Bowden kicked a penalty before the interval and then converted Jerome Kaino's score - the back-rower touched down off the back of a five-metre scrum - soon after to make it all square before slotting another penalty to edge the visitors ahead.
But Cruden levelled with another penalty and then number eight Mike Leitch broke out from inside his own 22 resulted in a try for Tom Marshall. New Zealand fly-half Cruden again added the extras and sealed matters with a further penalty.
Blues replacement Ihaia West kicked a penalty after the full-time siren to earn his team a consolation bonus point.
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