The Brumbies were left reeling at Canberra Stadium on Saturday night when the Durban Sharks scored an after-the-siren try to snatch a 27-22 win.

It's the first time since 1999 the Brumbies have lost the first two games of a season.

But the new-look side has two losing bonus points and has shown glimpses of brilliance to suggest the players are capable of getting things back on track.

The Brumbies defended for most of the night as they battled a determined Sharks side and a mounting penalty count against theml, as referee Angus Gardner punished the slightest error.

In the end it was a hail mary play from the Sharks that won the match as the visitors played for 60 seconds after the siren before a Curwin Bosch kick bobbled past Brumbies defenders and into Lukhanya Am's hands for the match-winner.

The Brumbies scored three tries to two and appeared the likely team to win when scores were locked at 22-all with less than three minutes to go.

But they failed to execute close-range opportunities and a drop goal attempt from back-up playmaker Isaac Thompson, who was on debut, missed its target with time running out.

The five-point loss to the Sharks followed an opening-round defeat to the Canterbury Crusaders.

"The guys worked pretty hard for each other ... we got ourselves back in the game and then we had a chance to win it," Larkham said.

"The effort again was tremendous so there are a lot of positives. But we're not looking for positives, we're looking for realism. We don't like losing.

"We're not a team that loses traditionally, so we've got to be better in the last five minutes of the game."

The Brumbies had a try disallowed in the first half despite Gardner initially awarding the five-pointer when Josh Mann-Rea dived over from close range.

One of Gardner's sideline assistants said there was a knock-on in the lead-up play and Gardner backed his judgement and gave the Sharks possession.

The Brumbies opened up a 15-3 lead in the first half and looked like they were going to blow the Sharks away.

But the Sharks strangled their way back into the contest and took advantage of Kyle Godwin being sent to the sin bin for a professional foul to open up a seven-point lead.

The Brumbies levelled when Tevita Kuridrani scored next to the posts and it triggered a frantic last 10 minutes of the match.

In a cruel twist, the Sharks took advantage of Thompson's missed shot and went 100 metres to score in injury time.

"It was tough, we're about winning and we don't really like losing," Carter said.

"There were a few positive things there, but two weeks in a row we've let ourselves down in the final moments.

"We fought back in the second half and hardly had any ball ... we rallied and got the score even. We just couldn't capitalise on the opportunities we had in the last 10 minutes."

Sharks skipper Patrick Lambie booted his team to victory, finishing with five penalties and a conversion.

"I feel for the Brumbies, I think it was a great game of rugby but we're over the moon to get the win, you could see the excitement," said Sharks captain Patrick Lambie.

The 8738-strong crowd erupted with frustration every time Gardner penalised the Brumbies, with the tally against the home side rising to 10 by the end of the match.

The Brumbies must now beat the Western Force at Canberra Stadium on Friday night to turn their season around and save it from an early-season stumble.

AT A GLANCE

DURBAN SHARKS 27 (Tendai Mtawarira, Lukhanyo Am tries; Pat Lambie 5 penalties, conversion) bt ACT BRUMBIES 22 (Henry Speight, Josh Mann-Rea, Tevita Kuridrani tries; Wharenui Hawera penalty; Wharenui Hawera, Isaac Thompson conversions) at Canberra Stadium on Saturday night. Referee: Angus Gardner. Crowd: 8738.