The Dutchman says he believes the 2019 Tour de France route is "far from ideal" and doesn't play to his strengths. Dumoulin thrives off time trials and more manageable mountain top finishes, but next year's Tour has just 27km of individual effort against the clock and numerous high-mountain finishes over 2,000m.
Winner of the Giro in 2017, the 28-year-old could return to the Italian race despite wanting to better his second place to Geraint Thomas at the Tour this year. The Giro route features significantly more time trialling, including two short time trials on the opening day and on the final day in Verona. Stage nine will also feature a 34.7km time trial from Riccione to San Marino.
"The route of the Tour de France is far from ideal for me," Dumoulin told De Telegraaf. "I don't think there has been a Grand Tour in recent years that fits my profile so badly."
"In every respect, the Giro is much better for me. On the other hand, I won the Giro once, and after the second place behind Geraint Thomas last summer my big target is to win the Tour."
Dumoulin has just returned from his honeymoon in Nepal and is beginning preparations ready for the 2019 season. He said he will need to outline as soon as possible which race to target with the team, but says it is unlikely he'll ride the Giro and Tour back to back as he did in 2018.
"At the end of July I clearly stated that [the Tour] would be my big goal. I wonder now whether I should put everything on the Tour in 2019.
"After initial discussions with the team we tend to choose a Grand Tour. I currently do not really have a preference, so the team has the decisive vote. We will soon make that decision because the whole program depends on that choice.
"To ride the combination Giro and the Tour again? After this season I know how hard it is and it is far from ideal to ride two Grand Tours every year. "
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