The 26-year-old Czech rider picked up the biggest win of his career after attacking from a select group seven kilometres from the finish of the 252km race in the hilly Limberg region of the Netherlands.
Pre-race favourite Peter Sagan (Cannondale) was nowhere to be seen as the remainder of the field fought for second place, with Spaniard Alejandro Valverde (Movistar) pipping Australian Simon Gerrans (Orica-GreenEdge) to complete the podium.
The much fancied Belgian rider Philipe Gilbert (BMC) - who became world champion on a near-identical course at Valkenberg last September - crossed the line in fifth place after Poland's Michal Kwiatkowski (Omega Pharma-Quick Step).
Italian defending champion Enrico Gasparotto (Astana) settled for ninth place behind Columbian Segio Henao (Team Sky), Belgium's Bjorn Leukemans (Vacansoleil-DCM) and Dutchman Pieter Weening (Orica-GreenEdge).
Joaquim Rodriguez (Katusha) and Thomas Voeckler (Europcar) both withdrew from the race after heavy falls, the Frenchman reportedly suffering a broken collarbone.
Unlike the majority of races this spring, the opening classic of the Ardennes week was played out under blue skies and balmy temperatures that even crept above the 20-degree Celsius mark.
For the second year running fans were treated to a surprise with the sight of outsider Kreuziger crossing the line a full 22 seconds ahead of his nearest rival. It was Kreuziger's first victory for new team Saxo Bank-Tinkoff after joining Bjarne Riis's outfit in the close season after two troubled seasons at Astana. Kreuziger also became the first Czech rider to win the Amstel Gold Race in its 48-year history.
"It was a big surprise but the team was excellent today and I'm really happy to take the crown from my friend Enrico Gasparotto who won last year," Kreuziger told reporters before mounting the podium and downing the traditional race winner's pint of Amstel beer.
Kreuziger made his decisive attack from the remnants of a nine-man break on the penultimate climb of the day, the Bemelerberg, inside the closing 10 kilometres of the race. Damiano Caruso (Katusha), Lars Petter Nordhaug (Blanco), Andriy Grivko (Astana) and Weening couldn't match the Czech for pace and were soon caught by Giro d'Italia champion Ryder Hesjedal ahead of the final ascent of the infamous Cauberg climb.
Kreuziger held a 26 second advantage over the returning peloton as he started the Cauberg - and held on to much of his advantage despite a spirited chase led by Gilbert in the rainbow jersey.
"I could only hear the people call my name on the final climb and I gave it my best," Kreuziger replied when asked to describe his emotions on the Cauberg. "I knew I had 20 seconds going over the top and so I thought I could do it."
And do it, he did. Grimacing with pain, Kreuziger time trialled his way along the flat 1.7km run-in to Valkenberg before raising his arms aloft for his first win since taking stage 19 of last year's Giro.
Gilbert, who was caught up in the crash which saw Voeckler taken to hospital with 90km remaining, led out the sprint for second place but was brushed aside by Valverde and Gerrans on a day which refused to keep to the script.
Garmin-Sharp's Johan Vansummeren instigated the day's main break after the towering Belgian put in an early attack not long after the race rolled out of Maastricht. Vansummeren was joined by Mikel Astarloza (Euskaltel), Tim De Troyer and Nicolas Vogondy (Accent Jobs-Wanty), Alexandre Pliuschin (IAM), Arthur Van Overberghe (Topsport Vlaanderen), Klaas Sys (Crelan-Euphony).
The seven-man break built up a commanding lead of eleven minutes before some hefty pace-setting by Blanco saw the advantage drop fast. With 55km remaining, Vansummeren, Astarloza and Pliuschin rode clear on the Loorberg; 10km later, Spanish veteran Astarloza went alone after a big dig on the Gulpenerberg - one of the largest of the 34 climbs on the menu.
With Voeckler by now already in an ambulance and Andy Schleck (RadioShack-Leopard) having himself thrown in the towel after being distanced in the same incident, Spain's Rodriguez was involved in a nasty looking crash on a muddy downhill bend involving Michael Matthews of Orica-GreenEdge and Vacansoleil's Rob Ruijgh.
Rodriguez, one of the pre-race favourites, was forced to retire from the race and is now a doubt to defend his Fleche Wallonne title on Wednesday.
Reliving the glory days, Astarloza held a two-minute lead with 20km to go but he was caught shortly after the penultimate ascent of the Cauberg. Kreuziger had attacked from the pack on the Cauberg and joined Astarloza with five other riders on the Bemelerberg, 15km from the finish.
With the leading group starting to show a bit of indecision as the pack closed in, Kreuziger took matters into his own hands with his decisive break 7km from the finish.
It was to prove a worthy winning move.
- Sports & Recreation