Dumoulin had shown he was on form when racing against the clock, twice finishing runner-up to Tony Martin at the Tour de Suisse's time trials.
"I am so happy with this result," Dumoulin said after claiming the first Dutch national title for Giant-Shimano. "Red, white and blue for the coming year it is. I had my eye on this race for a little while and following the Tour de Suisse and with two second places there, I knew that I was in good form."
Making his win all the more impressive on the 47.8km course around Zaltbommel was that Dumoulin crashed on the first lap but explained the calming influence of Marc Reef in the car behind him was decisive as he composed himself and rode away to victory.
"I had Marc Reef coaching me behind to stay calm and that helped me a lot. The team have been great in supporting me and with the Giant Trinity TT bike I have a superb machine which helps too."
"Tom did a great job today to stay calm after he crashed and make sure he still paced himself. He was really focused and super smooth out on the course," Marc Reef said at the conclusion of the race.
In 2013 Dumoulin was second in the national road race behind Johnny Hoogerland (Androni Giocattoli) and third in the time trial and as Reef explained, the team is happy with how the 23-year-old is developing ahead of his second consecutive appearance at the Tour de France.
"It is a great reward for the hard work he has put in, both on his own and with the team's coaches and trainers to develop and get stronger," Reef said. "With Tom we have a well structured plan in place for his development and he is going from strength to strength."
Dumoulin will debut his new national kit on on the Tour's 54km stage 20 time trial from Bergerac to Périgueux.