Ciolek proved to be the fastest in a six-way sprint at the end of a race hampered by snow, rain and freezing temperatures, the 26-year-old powering clear of Slovak sensation Sagan and Swiss veteran Fabian Cancellara (RadioShack-Leopard) in the closing straight.
It was the biggest win of the 26-year-old Ciolek’s career, which appeared to have nosedived following his last major victory - in the 2009 Vuelta a Espana. Ciolek's win - the first for Germany since Erik Zabel's fourth Milan-San Remo scalp in 2001 - also marked a first major victory for Africa’s first Professional Continental team, MTN-Qhubeka, which launched in the off-season and was given a wildcard entry for this, the first of five 'Monuments' of the classics season.
"It's unbelievable," said Ciolek after crossing the line. "This is an unbelievable success for us and just an incredible day. We just came here as a wildcard and now we're standing here with the trophy. This is great. I knew I had to follow all the best riders on the Poggio and it worked out perfectly."
Frenchman Sylvain Chavanel (Omega Pharma-Quick Step) took fourth place ahead of Italian Luca Paolini (Katusha) and British national champion Ian Stannard (Team Sky).
Ciolek’s unexpected win was a suitably dramatic end to a chaotic 104th edition of “La Classica di Primavera”. Taking place on a Sunday for the first time in 31 years, the 2013 Milan-San Remo started under grey clouds and freezing temperatures. Heavy snow on Passo del Turchino forced organisers to neutralise the race after 117 kilometres and bypass the first climb of the day with a bus transfer.
Riders who rushed into team buses at Ovada were photographed with layers of solid ice on their helmets. Some were reportedly reduced to tears.
The race was further delayed when it was decided that the infamous Le Manie climb – often so decisive in making an initial selection – was also too dangerous to be included in the traditional parcours.
Two hours later, the race resumed in the coastal town of Cogeleto, 126.5km from the finish, with the initial six-man break – which had formed early on in the day as the riders rolled out of Milan – holding onto their 7’10” advantage built up in the first ‘stage’ of the race.
The escapees – Italians Filippo Fortin (Bardiani Valvole), Matteo Montaguti (Ag2R-La Mondiale) and Diego Rosa (Androni Giocatto), Russian Maxim Belkov (Katusha), Dane Lars Bak (Lotto-Belisol) and Spain’s Pablo Lastras (Movistar) – had held a maximum lead of 12’30” before the neutralised section, with the Cannondale team of Sagan and the Astana team of Vincenzo Nibali combining to reduce the arrears on learning of the decision to shorten the race.
Once the six leaders had been given back their advantage, the chasing peloton zipped out of Cogeleto, each rider covered head-to-toe in waterproofs and extra layers to ward off the cold. Some big names – including Belgian classics specialist Tom Boonen – decided to quit the race instead of returning to the saddle after the enforced break.
The rain continued to lash down as the peloton ate into the advantage of the six leaders. With the length of the race reduced from 298km to 243.5km, there was more urgency from the main pack.
But the scrapping of two key climbs played into the hands of the sprinters and did not work in the favour of Nibali, who struggled constantly with the cold and eventually threw in the towel 40km from the finish. 2011 winner Matt Goss (Orica-GreenEdge) also withdrew from the race following injuries sustained in a crash before the neutralised zone.
Back on the front of the race, and Fortin was the first of the leading sextet to crack, the young Italian dropping back with 75km remaining as the advantage fell below the five-minute mark.
Bak, who struggled constantly with cold hands and cramps, put in a big dig on the third of the ‘tre capi’, the Capo Berta, which saw both Montaguti and Lastras tailed off. With 30km left to race, all the escapees had been reeled in by the pack – just as a crash in the peloton saw Sky’s Geraint Thomas and Garmin-Sharp’s Tyler Farrar hit the deck.
Sky’s afternoon got worse when Norway’s Edvald Boasson Hagen cracked on the Cipressa climb 25km from the finish. World champion Philippe Gilbert attacked on the descent of the climb, forcing a reaction from Chavanel, Stannard and Russian national champion Eduard Vorganov (Katusha).
Gilbert dropped back into the peloton, but the Stannard trio started the final climb of the day with a 30-second advantage over the chasing pack. Vorganov was first to crack, the Russian swept up by a counter attack by Astana’s Maxim Iglinsky.
On the precipitous slopes of the Poggio a select chasing group formed around Sagan and Cancellara, with Ciolek present alongside Filippo Pozzato (Lampre-Merida) and Luca Paolini (Katusha). Pure sprinters such as Mark Cavendish (Omega Pharma-QuickStep), Alessandro Petacchi (Lampre-Merida) and Andre Greipel (Lotto Belisol) were easily distanced, while defending champion Simon Gerrans (Orica-GreenEdge) couldn't stick with the pace-setters.
Sagan, Cancellara, Ciolek and Paolini caught Chavanel and Stannard with 3km remaining on the outskirts of San Remo. Sagan put in the first attack just over 2km from the finish. Just as the 23-year-old was pegged back, Stannard powered clear in a huge gear to open up a small gap.
But the British powerhouse was caught under the 1km-to-go banner setting things up for a thrilling bunch sprint on the Ligurian coast.
Sagan launched the sprint and looked to have the race in his pocket before a delightful late surge by Ciolek produced a major upset. After two successive runner-up sports in Milan-San Remo, Cancellara settled for the third rung on a podium he last topped in 2008.
BMC’s Taylor Phinney came from nowhere to take seventh place, while Alexander Kristoff (Katusha) edged Cavendish to take eight place as the main chasing pack came home 14 seconds in arrears.
MTN-Quebeka team manager Douglas Ryder was thrilled by his team's success in the face of more established WorldTour outfits and illustrious riders.
"To win the first major classic ahead of Peter Sagan and Fabian Cancellara through these weather conditions is amazing," he said. "We were coming into the race hoping for a top 20 but every rider gave everything they could to help Gerald."