The Rebels scored two second-half tries in four minutes to stun the Crusaders and secure a rousing 28-19 home victory in their Super Rugby match in Melbourne on Saturday.
Fired by a brace of tries from scrumhalf Nick Phipps and incisive kicking from veteran back Mark Gerrard, the Rebels kept the Crusaders scoreless for an entire half to register only their third win of the season in front of an ecstatic crowd of 18 000.
The Crusaders' shock loss weakened their position in the southern hemisphere provincial tournament's top six and was compounded by injury to number eight enforcer Kieran Read, who limped off the turf gingerly at the start of the last quarter after a heavy fall in a lineout.
"We said that we'd set a bit of standard how we wanted to play the game," the Rebels' Welsh captain Gareth Delve said in a pitchside interview, referring to his team's gallant loss to the powerful Pretoria-based Bulls in their previous match.
"To hold a fantastic team like the Crusaders scoreless in the second half is amazing and shows that we're making some progress.
"The confidence is building in this team and it makes such a massive difference."
The Crusaders held a 19-10 lead at halftime, but Phipps's 66th-minute try and Stirling Mortlock's five-pointer shortly after broke the game open, and the Rebels marched to their finest victory since joining the 15-team tournament last year.
The hosts started brightly with Phipps snatching the ball out of a ruck near the posts and breaching the Crusaders defence with a low dive over the line in the 12th minute.
Flyhalf Tom Taylor, who kicked the Crusaders to a tight win over reigning champions the Reds last week, slotted two penalty goals to steady the visitors.
The Crusaders struck 10 minutes before the break, spreading the ball wide to fullback Tom Marshall who made a dart for the left corner but was pulled down in a tackle two metres shy of the line.
Lock Sam Whitelock thundered in to scoop up the ball, however, and cantered over unopposed to put the Crusaders in front, with Tom Taylor adding the conversion and another two penalty goals to extend the lead to 19-10 at halftime.
The Rebels re-doubled their efforts after the break, gleaning two penalty goals to Beale who kicked the home side to within three points in the 55th minute.
With tension rising to fever pitch, veteran back Mark Gerrard charged through a pack of players and shipped the ball inside to Phipps, who streamed over next to the right post to put the Rebels in front with 14 minutes left.
Former Wallabies captain Mortlock, a late substitute, intercepted an ill-directed pass from Owen Franks and fed winger Cooper Vuna, who was held up just before the line.
Vuna's offload found Mortlock, who cantered over for the sealing try to spark thunderous cheers from the terraces.
The Rebels' defence, traditionally their Achilles heel, stayed resolute for the final 10 minutes and flanker Richie McCaw fumbled the ball after the siren to conclude the match and cap a disappointing night for the Crusaders' captain in his first start of the season.
Melbourne Rebels – Tries: Nick Phibbs (2), Stirling Mortlock. Conversions: Kurtley Beale (2). Penalties: Beale (3).
Crusaders – Try: Sam Whitelock. Conversion: Tom Taylor. Penalties: Taylor (4).