He placed third in 2007 and second in 2010. Today, the 36-year-old will try to help Colombian team-mate Fernando Gaviria sprint to victory against favourites like Peter Sagan (Bora-Hansgrohe) and 2016 winner Arnaud Démare (FDJ).
"[Oscar] Freire beat me in a straight sprint that day [in 2007]," said Boonen. "I was on [Alessandro] Petacchi's wheel but he just didn't have the legs and blocked me when he needed to go. Freire went on the left and I was blocked on the right. But that's Milan-San Remo. It's a seven-hour race and then it's decided in two seconds."
The race rolls out of Italy's financial and fashion capital this morning at 10:00 local time. The riders cover 7.4 kilometres over Milan's paving stones and tram tracks before arriving at kilometre zero.
The 291km race rolls through the Po Valley, climbs the Passo Turchino to Liguria and has a steady crescendo as it travels west along the coastline to San Remo.
The sun shines warmer in Milan than on the casino town of San Remo today. Wind will blow gently from the north and the mercury will reach 15°C later this afternoon.
"A lot of people think that there's a lot of time, but sometimes is goes very fast. They think that from Milan we just ride to the coast, but when it's windy, it's hard. Some riders are dead when they hit the coast," added Boonen.
"You have to stay focused and not use too much energy. It's really seven hours of racing, it’s not just the last to hours you see on television."
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Along the coast, the riders climb the three capi, the Cipressa and Poggio. At the top of the Poggio there is 5.4km, half downhill and half along the flat, to San Remo.
"Milan-San Remo's not a difficult race. They go up the Poggio as fast as possible and down as fast as possible, and then they sprint, but there's always... Every five or six years, there's something that happens that you didn't expect, so we'll see. We have to be prepared for everything."
As Quick-Step showed in Tirreno-Adriatico's sixth stage, it has men to attack and sprint. Niki Terpstra launched from far, drew out Sagan, and Gaviria waited to win the sprint.
Gaviria fell in training on Thursday, hurting his wrist, but the team doctor said that he should be fine for today’s race.
He debuted in Milan-San Remo at 21 years old last year and seemed able to win until he crashed at 300 meters from the finish. Boonen said that Gaviria has the defining characteristics of "true champion."
"He's fast, he's good and he's one of the most talented guys in the team for his age. It's only right that he gets a chance to win," Boonen continued.
"Maybe in 10 or 15 years we'll be standing here with him and asking why he never won Milan-San Remo, while everybody would have thought he'd win it five times.
"You have to take your chances you get. He's in good shape and we can put him a good position this year, so he's got to try to take it.
>>> Milan-San Remo 2017 start list
"There's language barrier, he only speaks a few words in Italian and his English is improving, but is not enough to have a conversation with him. He's improving and learning everything, including how the team works. You can see that it all flows naturally for him.
"He has the brains to make a decision on his own, as he did in the sprint when he won the stage [on Monday]. That defines a true champion."
A Colombian, or anyone from North or South America, has never won the Italian monument. Two Brits Mark Cavendish and Tom Simpson have their names on the list of winners. Belgian cycling great Eddy Merckx holds the record with seven wins in San Remo.
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