Dumoulin abandoned the Giro following a crash on Stage 6 that resulted with him getting a piece of debris embedded in his knee, and even after initial surgery it was revealed that the incident had caused damage to a tendon that required long-term rehabilitation.
The 28-year-old had been expected to challenge for the Tour de France, but was forced to skip the race, and Dumoulin's coach has now confirmed that the rider is out long-term, meaning he is unlikely to feature in the two major events remaining in the 2019 men's road cycling calendar.
In a report in de Telegraaf, Dumoulin's coach Hendrik Werner said: "The most important thing is that his knee recovers completely again. Tom knows what to do to start a Grand Tour in top form. Furthermore, he also has the experience of racing a Grand Tour at the top of the leaderboard.
It is not as if he has missed classes in school. This long period of rest will only increase his hunger for success.
"He now knows what it is to be on the sidelines during the main period of the season. Just think how he will want revenge once his knee is 100 per cent in order again. And then he will be fresh at the start both physically and mentally."
'It was okay until I stood up on the pedals' - Dumoulin talks about withdrawal
The coach of the Netherlands men's national team also confirmed Dumoulin's expected absence from the World Championships in Yorkshire in September, saying:
"It makes no sense to talk to him [Dumoulin] about the World Championships."
La Vuelta runs from August 24 to September 15, with the World Championships following later in September from Sunday 22 to Sunday 29. Both events will be live on Eurosport and Eurosport Player.