The Reds put on their best performance of the Super Rugby season to beat the high-flying Chiefs 42-27 in a nine-try humdinger in Brisbane on Sunday.
The Chiefs dominated the first period to race into a 22-8 lead but a try from Ben Lucas after the half-time hooter sparked a massive comeback from the defending champions, who scored 28 unanswered points to snatch the initiative back.
The result is the Chiefs' first defeat since Round One back in February and sees the Reds climb to second place in the Australian conference.
A four-try bonus point leaves the Chiefs one point behind tournament leaders the Bulls.
14 points down with the interval looming large, the Reds looked in trouble but skipper James Horwill took the brave decision to push for a try with the last play of the half. The gamble paid off as Lucas crossed to add to Dom Shipperley's opening score in the early stages and drag the hosts back into contention.
It proved a pivotal moment as the Reds proceeded to run in three more tries in ten minutes after the break as the shell-shocked Chiefs defence wilted.
The defeat was compounded for the Chiefs with the sight of centre Richard Kahui leaving the field in the first half with a dislocated shoulder.
The game was not without controversy however. The Chiefs will have reason to feel aggrieved after Luke Morahan escaped a yellow card for a tip-tackle on Sonny Bill Williams on 66 minutes. None of the officials were able to see his number though and the full-back went on to make two try-saving tackles when he should have been in the sin-bin.
Whether it would have changed the result is debatable however as the Reds showed cool heads in the last quarter, even landing a drop goal via Mike Harris to keep the Chiefs at a safe distance.
Teenage openside flanker Liam Gill was immense for the home side, pilfering time and again while Harris was again instrumental with the boot for the Reds, landing seven from eight attempts at goal.
The Reds were on the board after just four minutes, with Harris intercepting, drawing three in a run to the line before offloading for Dom Shipperley to score in the corner.
Williams was outstanding for the Chiefs and scored in the 30th minute, running over untouched for the first of the visitors' three tries in eight minutes.
Liam Messam and try-machine Sona Taumalolo added their names to the scoresheet as the Chiefs streaked ahead.
But after Lucas scored, the Reds drew level immediately after half-time, putting on 15 pick-and-drive phases for Scott Higginbotham to crash over.
Will Genia made it two tries in the first five minutes of the second half with a brilliant solo effort, splitting defenders before pinning back the ears and beating Lelia Masaga to the corner.
Having secured their first four-point bonus try of the season, the hosts took just moments to add their fifth, this time through replacement hooker Saia Faingaa, who crashed over at the back of a driving maul.
A late try from wing Asaeli Tikoirotuma was the Chiefs' only reply.
Tries: Shipperley, Lucas, Higginbotham, Genia, S. Faingaa
Cons: Harris 4
Pens: Harris 2
Tries: S.B. Williams, Messam, Taumalolo, Tikoirotuma
Cons: Cruden 2
Reds: 15 Luke Morahan, 14 Dom Shipperley, 13 Anthony Faingaa, 12 Mike Harris, 11 Digby Ioane, 10 Ben Lucas, 9 Will Genia, 8 Scott Higginbotham, 7 Liam Gill, 6 Jake Schatz, 5 James Horwill (c), 4 Rob Simmons, 3 James Slipper, 2 James Hanson, 1 Ben Daley.
Replacements: 16 Saia Faingaa, 17 Greg Holmes, 18 Adam Wallace-Harrison, 19 Eddie Quirk, 20 Beau Robinson, 21 Nick Frisby, 22 Rod Davies.
Chiefs: 15 Andrew Horrell, 14 Lelia Masaga, 13 Richard Kahui, 12 Sonny Bill Williams, 11 Asaeli Tikoirotuma, 10 Aaron Cruden, 9 Brendon Leonard, 8 Alex Bradley, 7 Tanerau Latimer, 6 Liam Messam, 5 Brodie Retallick, 4 Craig Clarke (capt), 3 Ben Tameifuna, 2 Mahonri Schwalger, 1 Sona Taumalolo.
Replacements: 16 Hika Elliot, 17 Toby Smith, 18 Kane Thompson, 19 Sam Cane, 20 Augustine Pulu, 21 Jackson Willison, 22 Robbie Robinson.
Referee: Marius Jonker (South Africa)