Boosted by a double to All Blacks lock Brodie Retallick, the injury-stricken Chiefs have battled their way to a 41-28 Super Rugby win over the Bulls in Hamilton.

The Bulls proved unstoppable in Friday's first half, leading 28-14 at the break, but the Chiefs kept the South Africans scoreless in the second spell as they ran in four tries.

Winger Warrick Gelant opened the scoring for the Bulls after just three minutes, but the early lead disappeared five minutes later when Johnny Fa'auli finished off a storming Chiefs move.

The Bulls were relentless in the opening 30 minutes, pounding the Chiefs' line and dominating territory and possession.

They were rewarded for their willingness to spin the ball wide in the 16th minute, winger Divan Rossouw showing impressive strength to dive over in the corner.

Rossouw grabbed a second seven minutes later, the Bulls looking set to take a 21-7 lead into halftime until Retallick bulldozed over from close range in the 36th minute.

But an aimless pop kick from Chiefs halfback Brad Weber two minutes later let the Bulls back in. Junior Springboks halfback Embrose Papier made the initial break which was finished in style by Handre Pollard between the uprights.

The Bulls' 28-14 halftime lead lasted only three minutes before the Chiefs struck, lock Mitchell Brown barging over from a lineout drive and Damian McKenzie's boot narrowing the visitors' lead to seven.

The Chiefs edged closer in the 55th minute when Retallick grabbed his second, then hit the front through McKenzie's 63rd-minute penalty goal.

The game was all but over in the 68th minute when the Bulls were reduced to 14 men, replacement prop Conrad Van Vuuren lucky to receive only a yellow card for his a late high tackle on McKenzie.

Solomon Alaimalo chased down Fa'auli's chip kick to extend the Chiefs' lead to six points in the 73rd minute, with Anton Lienert-Brown's stoppage-time try completing an impressive second 40.