If not for a ten minute time penalty for a doping infraction in 1977, he would have finished in the top 5 in each of the first 12 Tours he entered.

He won the World Professional Road Championship in 1985 at the age of 38, with a late attack surprising the favorites of LeMond, Roche, Argentin and Millar.

[6] He joined the Swift club in Leiden and made a fast impression, winning youth races in his first season.

[7] He also won a gold medal at the 1968 Summer Olympics in Mexico City in the 100 km team time-trial with Fedor den Hertog, Jan Krekels and René Pijnen.

[7][9] Initially he was riding in support of team leader Roger De Vlaeminck, but the Belgian abandoned the race due to a crash near the end of the first week.

On stage 10 however, Ocaña stole the show in one of the most memorable attacks in Tour history taking the jersey from Zoetemelk and distancing all of the other favorites.

On stage 14 Ocaña and Zoetemelk were involved in one of the most famous crashes in Tour history on the Col de Menté.

He wore the yellow jersey for the second time after winning the Prologue in the 1973 Tour de France, which took place in his home country of the Netherlands.

In the 1976 Tour de France he won stage 9 up Alp d'Huez by :03 in a hard-fought climb where he and Van Impe dropped all other riders and were alone crossing the finish.

He rode strongly and kept his narrow lead, which he would hold for several stages before losing it to Hinault on the final time trial.

Zoetemelk survived with four other riders in the winning group, won 3:45 over the next finishers and moved into the yellow jersey, which he would hold for 6 stages.

Hinault withdrew and Zoetemelk remained the strongest rider in the Tour despite suffering a violent crash on Stage 16 which cut his arm and leg open.

While he was in his late 30s during his final Tours between 1982 and 1986 and was no longer a pre-race favorite he still remained the strongest GC general classification rider on his team and always had a respectable placing in the overall standings.

There were several early breakaways, but none of them included any riders considered threats to stay away and never extended their gap much beyond two minutes.

Hinault had an off day, suffered a flat tire and abandoned the race, as did several other strong riders including Hennie Kuiper, Dietrich Thurau and Urs Freuler.

Knowing he would not win a sprint against the youngest, strongest riders in the world he launched an attack with over a kilometer to go.

Going into the second to last turn Zoetemelk got to the front of the group, moved all the way to the outside of the road then swept back along the inside charging forward into the straightaway.

Perhaps, as he was by far the oldest rider in the group and considered long past his prime, his attack caught the surviving contenders by surprise and he quickly opened a gap of fifty meters.

As of 2020 Zoetemelk is still the oldest world champion in the history of this event[16] and of the other top 10 finishers in the 1985 race all of them were between 24 and 28 years old.

[17] Regarding his victory in the 1980 Tour de France, Peter Post, directeur sportif of the TI–Raleigh team in the Netherlands, approached Zoetemelk through his wife, Françoise, after the world championship in 1979.

Zoetemelk objected to claims that he had won only because Hinault had dropped out, saying: "Surely winning the Tour de France is a question of health and robustness.

Gerald O'Donovan, the TI–Raleigh director behind sponsorship of the team, said: Of one-day races he won La Flèche Wallonne in 1976, and the Grand Prix d'Automne in 1977 and 1979.

Of the major week long stage races he won Tirreno–Adriatico, the Tour de Romandie and three editions of Paris–Nice.

At his stage of his career, he was no longer a favorite for victory and was not taking substances for "performance enhancement", but just to "survive" the race.

His career coincided with the rise and fall of both Eddy Merckx and Bernard Hinault, riders considered by many to be the #1 and #2 in all of Tour de France history.

While Merckx was rivaled by Luis Ocaña and Hinault by Laurent Fignon and Greg LeMond, by the end of most of their Tour victories it was Zoetemelk who proved to be the only rider in the entire field capable of keeping either one of them within striking distance.

Zoetemelk stayed with Rabobank for 10 years, retiring as a directeur sportif and from the sport after the 2006 Vuelta a España.

Between 1972 and 1985, he won the Gerrit Schulte Trophy nine times as best rider of the year, more than anybody else in Dutch professional racing.