The Stormers put a horror Super Rugby tour of New Zealand behind them with a 30-22 victory over the Blues in Cape Town.
Trailing by nine points early in the second half, the South Africans finished strongly and were helped by the red-carding of New Zealander Matt Duffie on 67 minutes.
Success was particularly welcome for the Stormers after conceding 155 points in drubbings by Crusaders, Highlanders and Hurricanes.
"I told my boys after the tour that the main thing was to learn from our mistakes," said Stormers skipper and flanker Siya Kolisi.
"We were hurting after those heavy losses but remained positive and the extra effort put in this week paid off tonight.
"Having leaked a lot of soft tries in New Zealand, we defended heroicly at times against the Blues and that made a huge difference.
"Another key factor was the energy and commitment from our replacements when they came off the bench during the second half," added the Springbok.
Blues skipper and hooker James Parsons offered no excuses after seeing a three-match winning streak end having led 12-10 at half-time.
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"We lost the physical battle in the final 20 minutes and our discipline cost us dearly with two yellow cards and a red.
"Despite the loss, I was proud of my boys for the heart and resilience they showed."
Success for Stormers gave them a 15-point lead over Pretoria outfit Northern Bulls in the Africa 1 log and they seem set for a home quarter-final.
Losing dealt the last-eight hopes of Blues a major blow as they trail Highlanders by five points in the fight for the last Australasian slot.
After Stormers fullback SP Marais kicked a penalty, All Blacks prop Charles Faumuina set up tries for centre George Moala and Parsons, one of which fly-half Piers Francis converted.
The decision of Kolisi to go for touch rather than the posts from a penalty was vindicated when he dotted down beside the post and Marais converted.
Blues stretched the lead to 19-10 when loose forward Blake Gibson grabbed an off-load from centre Sonny Bill Williams to go over and Francis converted.
Marais kicked another penalty before a tap-and-go penalty from fly-half Dillyn Leyds caught the visitors napping and his try was converted by Marais.
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Winger Duffie, sin-binned in the first half, received a second yellow card followed by an automatic red when he fell on Stormers winger Cheslin Kolbe.
The South Africans used their numerical superiority to good advantage with a try from replacement forward Sikhumbuzo Notshe and a conversion and penalty from Marais.
All the New Zealanders could manage in return was a penalty from Bryn Gatland, who had replaced Francis as playmaker.