Chris Froome lost 37-seconds to Tom Dumoulin in the opening time trial of the 2018 Giro d’Italia on Friday. Conventional wisdom tells us this is no big deal.

“There is plenty of time for Froome to make up this margin. The race is 21 stages long, and we still have the mountains! It’s way too early to count anybody out! Anything can happen!”

However, after taking a deeper look at trends from the recent past, conventional wisdom proves to be incredibly wrong, and this time loss seems much more significant than appears at first glance.

Citing the fact that we are three stages into a 21-stage race is a bit misleading. Time gained or lost on the first stage is equally significant to time gained or lost in the first week. I’m of the belief that both fans and teams tend to overvalue potential time gaps in the third week of a grand tour, while greatly undervaluing the chances to gain time in the first week. A second on day one is equal to a second on day 21.

Since 2015, five out of nine grand tours have been decided by less than a minute. In last year’s Giro d’Italia, a gap of 40 seconds separated the entire podium. While casual observers assume that even though margins are tight in the opening stages and we’ll see major gaps open up in the mountains, these stages rarely serve up the time gaps they would expect.

Below is a graph showing the winning margin in every grand tour since 2015. A quick glance will tell you that 40-seconds is a significant margin of separation.

If Froome’s loses this year’s Giro d’Italia by his current deficit, it wouldn’t be the first time a recent grand tour was decided by an opening time trial. The 2016 Tour de France opened and closed with the opening time trial in Dusseldorf. Eventual second-place finisher Rigoberto Uran ceded 51 seconds to Froome over the 14-kilometer course. After three weeks and 21 stages of racing, the Colombian rolled into Paris 51 seconds behind Froome.

Furthering the seriousness of this time gap is that the Giro organizers dialed back the number of traditional climbing stages in the Dolomites and placed a greater significance on the time trials in an attempt to court Froome and Dumoulin. The irony of this is that a course tailor-made for Froome could end up being his undoing.  We’ve seen he hasn’t been on the same level as Dumoulin in the race against the clock since the Dutchman absolutely crushed him at the 2016 World Time Trial championships.

It may seem counter-intuitive, but in a three-week grand tour, every second counts. The spontaneity and ample time gaps that so many fans expect simply aren’t that common, and the opening time trial is proving to be just as, if not more, important than a 7-hour, 6 categorized climb, queen mountain stage. Whatever happens, don’t be surprised if the top two places in the Giro ride into Rome in three weeks with less than a minute between them.