Rabobank's Luis Leen Sanchez won for the second day in a row to take the leader's yellow jersey from Bradley Wiggins at the Tour de Romandie.
Team Sky duo Wiggins and Michael Rogers are now second and third respectively heading into Sunday's concluding time trial in Switzerland.
They both finished in a reduced front group of around 40 riders as Spaniard Sanchez notched a clear-cut triumph in the sprint from Rinaldo Nocentini (AG2R) and Branislav Samoilav (Movistar) at the end the 184km fourth stage from Bulle to Sion .
He will take a nine seconds advantage into the undulating 16.5km time trial around Crans-Montana, with world TT silver medallist Wiggins and three-time world champion Rogers breathing down his neck.
It sets up an absorbing finale, with only 28 seconds separating the top 20 riders on the general classification.
Team Sky's had once again produced a strong display to defend Wiggins' yellow jersey on what was the queen stage of the race.
A group of six riders had escaped from the peloton after 25 kilometres on the ascent of the Col des Mosses and, despite a block headwind, Team Sky made sure their advantage never went much above three minutes.
Mark Cavendish and Geraint Thomas, winner of the opening prologue, did much of the work on the front and with their job done they dropped out of the race before the final 50km which featured two category one climbs.
Their team-mates had to be vigilant throughout that testing finale and they reacted quickly when a dangerous-looking group of four riders broke clear of the main group just as the original escape group was splintering.
That quartet forced Team Sky to really put the hammer down between the 40km and 30km mark, with Danny Pate, Kanstantsin Siutsou, Chris Froome and Rogers combining to reel them in ahead of the final climb up to St-Martin.
The pace meant that only 50 riders or so were left by that point and a succession of attacks off the front were kept under control by Richie Porte who set the perfect tempo at the front of the main group.
Heading down the sweeping descent before the flat run-in to Sion, Wiggins was perfectly positioned in a 12-man selection up front and he was soon joined again by Porte and Rogers who helped keep it all together.
Rabobank were also there in numbers and they were rewarded with the stage win thanks to another strong sprint from Sanchez.
It's now all about the final 16.5km on Sunday which includes a 4.3km drag up to Aminona which is graded as first category.