The Blues beat the Reds 31-24 in Brisbane on Friday to stay top of the Super Rugby Trans-Tasman table.

Leon MacDonald's side have now won four out of four in the competition, though they were denied a precious bonus point at Suncorp Stadium against the injury-plagued Reds.

Harry Wilson found a gap to score the opening try of the match for the home team, but Brandon Paenga-Amosa's yellow card for collapsing a maul proved to be a turning point.

Dalton Papalii and winger Mark Telea crossed over for the Blues in the space of seven minutes as MacDonald's charges took full advantage of the one-man advantage.

Patrick Tuipulotu and Finlay Christie were next to dot down for the leaders, either side of Paenga-Amosa's try, to give their side a 17-point advantage.

The Reds made a fight of it late on when a crosskick sent Filipo Daugunu over, soon followed by a successful penalty from the Fiji-born winger, but the comeback fell just short.

The Blues are one point better off than Super Rugby Aotearoa champions the Crusaders, who also made it four wins from four by defeating the Western Force 29-21 in Christchurch.

Scott Robertson's side were made to work hard for the victory after falling behind to Toni Pulu's well-taken try inside the opening four minutes.

Manasa Mataele finished soon after and Will Jordan slid over to complete a quickfire turnaround for the Crusaders, who went further ahead thanks to Whetu Douglas.

Ollie Callan's score from close range looked to have given the Force some hope, only for Sione Havili to cross the whitewash after the half-time hooter had sounded.

Jordan got his second of the game to give the Crusaders a 15-point lead and they stayed strong at the back until the final seconds.

Jordan Olowofela chased down Kyle Godwin's kick and went over, denying the Crusaders a bonus point in the process.