The Stormers put down a big marker about the championship potential with an impressive 34-26 win over the Chiefs on Saturday.
The Stormers outscored their opponents by four tries to three in a thrilling encounter at Newlands, ending the Chiefs' unbeaten run this season.
It also saw the men from Cape Town move to the top of the global standings - in 26 points, the same as the Crusaders, but with a better points differential.
The Chiefs stayed third in the New Zealand standings, two points behind pool leaders the Crusaders, but on course for a quarterfinal place.
The Stormers also put one of their darkest Super Rugby days behind them.
The Chiefs humiliated the Stormers 60-21 in a quarterfinal at Newlands stadium last season and this was the first meeting of the franchises since.
"We had not forgotten that thrashing," said Stormers skipper and flank Siya Kolisi after receiving the man-of-the-match award.
"Conceding 60 points in a knockout match was a deeply embarrassing experience for all of us and we vowed not to let it happen again.
"Apart from a fantastic effort by all my teammates, the noise of the crowd drove us on.
"Chiefs played their part in a match that must have been wonderful to watch. Some of their rugby was truly beautiful."
Chiefs skipper and flyhalf Aaron Cruden said: "I am proud of my guys for playing their part in a great game.
"They gave 100 percent effort right down to the wire as we sought to secure at least a bonus point from an epic contest."
After a thrilling first half in which the lead changed four times, the home side led 24-16 at half-time.
They stayed in front throughout an equally pulsating second half with a 35,000 crowd producing an electric atmosphere.
Chiefs pressed relentlessly in the closing minutes, seeking a score that would have given them a losing bonus point, but Stormers defended magnificently.
The New Zealanders scored two superb tries in the opening half with winger Toni Pulu rounding off a length-of-the-field handling movement for the first.
Pulu also scored the second, dotting down in the corner after a wonderful break by full-back Damian McKenzie from deep in his half took him past numerous Stormers.
Stormers scored an equally brilliant try 12 minutes into the second half to build a 34-21 lead.
Wing Dillyn Leyds broke clear and when tackled, flung a long back pass that fullback Sarel Marais gathered to race over.
Loose forward Sikhumbuzo Notshe, Kolisi, flyhalf Robert du Preez and Marais were Stormers try scorers and Du Preez kicked four conversions and Marais two penalties.
Pulu (two) and fellow winger James Lowe scored tries for Chiefs, Cruden slotted a conversion and two penalties and McKenzie a penalty.
Man of the match: Damian McKenzie provided the attacking spark, Toni Pulu the finishing while Brodie Retallick and Liam Messam added the muscle and niggle. Sarel Marais, Cheslin Kolbe and Dillyn Leyds produced the magic in the Stormers backline. Sikhumbuzo Notshe, Siya Kolisi, Eben Etzebeth and Bongi Mbonambi were the work-horses up front. However, our award goes to Stormers flyhalf Robert du Preez, who provided direction to his team with his outstanding reading of the game.
For the Stormers:
Tries: Notshe, Kolisi, Du Preez, Marais
Cons: Du Preez 4
Pens: Marais 2
For the Chiefs:
Tries: Pulu 2, Lowe
Pens: Cruden 2, McKenzie
Yellow card: Cobus Wiese (Stormers, 7 - foul play, late tackle)
Stormers: 15 Sarel Marais, 14 Cheslin Kolbe, 13 EW Viljoen, 12 Dan du Plessis, 11 Dillyn Leyds, 10 Robert du Preez, 9 Dewaldt Duvenage, 8 Sikhumbuzo Notshe, 7 Siya Kolisi (captain), 6 Cobus Wiese, 5 Chris van Zyl, 4 Eben Etzebeth, 3 Wilco Louw, 2 Bongi Mbonambi, 1 Jacobus Janse van Rensburg.
Replacements: 16 Ramone Samuels, 17 Oliver Kebble, 18 Frans Malherbe, 19 Jan de Klerk, 20 Nizaam Carr, 21 Justin Phillips, 22 Kurt Coleman, 23 Dan Kriel.
Chiefs: 15 Damian McKenzie, 14 Toni Pulu, 13 Anton Lienert-Brown, 12 Stephen Donald, 11 James Lowe, 10 Aaron Cruden (captain), 9 Tawera Kerr-Barlow, 8 Michael Leitch, 7 Lachlan Boshier, 6 Liam Messam, 5 Brodie Retallick, 4 Dominic Bird, 3 Atu Moli, 2 Hika Elliot, 1 Kane Hames.
Replacements: 16 Brayden Mitchell, 17 Siegfried Fisi'ihoi, 18 Sosefo Kautai, 19 Taleni Seu, 20 Mitchell Brown, 21 Nankivell Nankive, 22 Sam McNicol, 23 Shaun Stevenson.
Referee: Jaco Peyper (South Africa)
Assistant referees: Jaco van Heerden (South Africa), Cwengile Jadezweni (South Africa)
TMO: Shaun Veldsman (South Africa)
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