Chiefs grind out win over Brumbies with 'relentless' defence

Brumbies coach Stephen Larkham says three soft tries dented their hopes of upsetting the Chiefs with their chances of a top-two Super Rugby Pacific finish over after a 31-21 loss.

Missed tackles and butchered opportunities deep in attack cost the Brumbies an opportunity to roll the competition leaders at GIO Stadium on Saturday night.

They were competitive early before 24 unanswered points saw the Chiefs blow the game apart.

The loss leaves the Brumbies fourth on the table and likely to remain in that spot with a win against Melbourne next weekend, setting them up for a home quarter-final against the Hurricanes.

And they might have to do it without captain Allan Alaalatoa, the Wallabies prop helped from the field in the second half with a calf injury in what would be a monster blow.

The Brumbies enjoyed 65 per cent territory in the first half but were stifled by the physical Chiefs defence, with lapses at the other end of the field crippling their chances of staying in the game.

"I actually thought we played quite well for most of the game, they defended exceptionally well inside their 22 (metres) and they took their opportunities quite well," Larkham said.

"There were three tries there they scored without basically a hand on them - that's 21 points.

"Our lineout, we struggled to deliver good ball again there tonight, without that platform sometimes it's difficult for us to get on to a bit of a roll.

"We defended some really good passages that over the last month or so we haven't defended as well.

"So good energy, the boys started in a good frame of mind and had good energy throughout the game."

A clever short-side run from No.8 Luke Jacobson and an intercept try for Cortez Ratima let the Chiefs take control, before All Blacks contender Shaun Stevenson slashed through the line within five minutes of coming off the bench to complete a run of 24 straight points.

That barrage took the score from 7-all to 31-7 before late tries from Corey Toole and Pete Samu narrowed the margin.

The Chiefs, who have ploughed through most of the competition this season and only lost once, physically imposed themselves on the Brumbies and broke tackles easily to eat up post-contact metres.

So often able to rely on their rolling maul to get them out of trouble, the Brumbies only found one try off the back of their lineout from six inside opposition 22m.

"Both teams had a lot to play for so to put on a performance like that is incredibly pleasing," Chiefs coach Clayton McMillan said.

"Our defensive effort was huge, we understand what feeds the Brumbies game, ill discipline, allowing them to play at the right into the field ... to stop their maul in particular was really strong.

"It was pretty relentless, the boys didn't stop and that was the most pleasing thing."

In a potential battle of the respective national team fullbacks, the Chiefs' No.15 Damian McKenzie got the points over Tom Wright, initiating much of their attack and shifting the ball around at will.

Alaalatoa found himself in the sin bin early for a high shot on Brodie Retallick, although the Brumbies held strong and only conceded one penalty goal while he was off the field.