Dumoulin started with the Sunweb organisation (then knows as Argos-Shimano) as a fresh-faced 21-year old and along the way racked up a number of high-quality titles including a world time trial championships, Olympic silver and the overall at the 2017 Giro d'Italia.
The 28-year-old Dutchman, who has had a difficult season and was forced to sit out this year's Tour de France with a knee injury, had two years to run on his Sunweb contract.
“As a rider you always search for the highest achievable and you constantly ask yourself whether you are still in the right place, what is the best team for you and where the best options and opportunities are," Dumoulin said.
"There has always been interest from other teams, that’s normal, but the facilities here have always made me not to speak with other teams. After the disappointment of missing the Tour and finding myself sitting at home, I started to consider that a new environment could be refreshing. That’s why I decided to focus on the interest of some teams. There were great offers and this phase of my career felt like the right time to take it.
“It really does hurt to leave. My heart is here and together we have achieved great things that I’m very proud of. I’ve proven with Team Sunweb that winning a Grand Tour is possible with this team and I have no doubt that I could do it again with them. I know that the grass will not always be greener than at Team Sunweb and I want to emphasise that without them, I could never have got to where I am today.
"I will always remain grateful for the opportunities that I have had, and the opportunity that the team now grants me to allow me to explore my options within a new team.”
CEO Richard Plugge confirmed that the deal was all about bringing his team competitively closer to Ineos.
"You'd better race with each other than against each other", he refers to the fights that Dumoulin fought with Primoz Roglic and Steven Kruijswijk. "We can now put together the strongest possible team in the fight against a team like Ineos. Making our dreams and ambitions come true is getting closer and closer."
While Jumbo-Visma is rightly celebrating the acquisition of Dumoulin, with the Dutch outfit about to field a general classification trio capable of upsetting the current Ineos stranglehold on the Tour de France, it will be interesting to be see how the pecking order changes at major events and how it will manage the inevitable tensions that come with having three riders capable of victories and podium finishes in Grand Tour races.