Wout Poels followed up his fourth place at Fleche Wallonne with victory in Liege-Bastogne-Liege on Sunday.
The Team Sky rider claimed his first classics triumph with a late sprint in the closing metres of the one-day race, Poels edging out Michael Albasini, Rui Costa and Samuel Sanchez on the line.
Victory is Team Sky's first monument triumph since entering the sport, and seals an impressive Ardenne Classics campaign for Poels.
In stark contrast to last weekend's warm temperatures for the Fleche Wallonne, Sunday's race was beset by snow and rain, slowing the pace of the peloton and increasing the threat of accidents.
As a result the sprint for the line came just before the final kilometre, plenty of riders threatening to make breaks earlier before being sucked back into the peloton.
Team Sky showed their intent as Michal Kwiatkowski made a break on the penultimate climb of Cote de Saint-Nicolas, but he was quickly caught ahead of the cobbled ascent of Cote de la Rue Naniot.
As the summit moved into sight the top four riders made their move, and Poels had just enough to edge the final sprint.