Brisbane Broncos boosted their chances of finishing in the top four of the NRL with a hard-fought 12-10 triumph over Cronulla Sharks at Suncorp Stadium.

In a tense match littered with errors, it was ultimately Jordan Kahu's penalty that proved decisive, sending the Broncos up to sixth and level on points with Sydney Roosters, who face St George Illawarra Dragons on Sunday, in fourth.

Brisbane took the lead when Darius Boyd intercepted Matt Moylan's risky pass and set Corey Oates in for his sixth try in as many matches against the Sharks.

Cronulla hit back in sensational fashion, working the ball through multiple pairs of hands before Valentine Holmes crossed, but Matt Lodge powered in to restore the hosts' advantage within three minutes of replacing Sam Thaiday.

A brilliant run from James Segeyaro created an opening for Holmes to touch down his second, but Chad Townsend missed a conversion that would have put the Sharks ahead.

Kahu's two-pointer nudged the Broncos clear in the 49th minute and they repelled three sets of six in the closing minutes to seal an important victory.