The Blues have secured home advantage for as long as they remain alive in the Super Rugby Pacific playoffs, but could be facing the journey into the knockout stages without a key attacking weapon. 

Wing Caleb Clarke is facing time on the sidelines after pulling up lame 53 minutes into the side's 21-19 win over the Brumbies in Canberra on Saturday night. 

On the Stan Sport commentary, sideline reporter Sonny Bill Williams said Clarke left the pitch crying, and Blues coach Leon MacDonald confirmed the star speedster had an issue with his left hamstring. 

"He's bitterly disappointed, it's written all over his face so, yeah, he's gutted," MacDonald said. 

"[Hamstrings] normally take time – especially when you're a speed athlete like Caleb." 

The injury is the second to impact the Blues backline in as many weeks, with centre Rieko Ioane also nursing a left hamstring injury, suffered during the win over the Reds at Eden Park last week. 

It took a last-play drop goal from the boot of Beauden Barrett for the Blues to come away with the win in Canberra and lock up the competition's top seed, after a late Brumbies try looked to have swung the match for the hosts. 

It was a tough encounter, with little chance to get continuity as penalties and scrum resets killed any progress. 

As Brumbies captain Allan Alaalatoa alluded to after the match, the hosts felt hard done by as they drew the ire of the referee's whistle – on the wrong side of a 16-5 penalty count and at one point being down to 13 men through two yellow cards. 

"I think some of those were our fault, but I reckon we'll get an apology or something like that later in the week," Alaalatoa said. 

The Blues were made to work for every point. Particularly in the first half, of which the majority was played inside Brumbies territory, the hosts only cracked once – when Stephen Perofeta laid on a nice pass to hit Barrett on the run and put him into a gap for the try. 

The Brumbies scored more tries than the Blues, but penalty goals from Perofeta allowed the Blues to keep putting points on the board, and the Barrett drop goal ultimately made the difference to secure the top seed going into the playoffs. 

"That was a big focus for us, we really wanted to finish first, MacDonald said. "That was a driver and this was a big challenge – one playing two, to be able to do that was always going to be huge for us. 

"There's a good chance the Brumbies are going to be there at the real pointy end of the season, so it was important we wanted to put on a good show. 

"There's a lot to be proud of. It wasn't a perfect performance in terms of execution, but in terms of effort and hunger and a little bit of heart, that's a 10/10 for me in a lot of those areas."