Theuns will head to Team Sunweb next season but wanted to sign off with a final win as thanks to the Trek-Segafredo team.
The 26-year-old Belgian and his teammates of two years had been trying unsuccessfully all week to beat Bora-Hansgrohe's Sam Bennett, who won four stages of the race. The Irishman gave Trek-Segafredo a hand on stage 6, crashing in the finale and leaving Theuns free to sprint to victory on his last day of racing in a Trek-Segafredo jersey.
"We had a good gap, and it was nice from Sam Bennett that he wanted to take a pull also. Then he passed in the last corner, inside, and I felt he was going really too fast," Theuns explained after the win.
"He crashed right in front of me, I had to brake full, get out of my pedal, get into my pedal again, but then I could go to [Matteo] Pelucchi's wheel and get the slipstream, and I had really a lot of power left in my legs."
The elusive win proved a major relief for Theuns after so many frustrating near misses.
"It was okay the whole week, I knew Bennett was faster in the sprint, but after yesterday (Saturday) when we made a mistake in the finale 200 meters, I was super, super disappointed," he said."So actually, yesterday evening and this morning I wasn't the most pleasant guy to be with. But now this has changed, and I really have to thank the team a lot, and we can have a good party tonight."
As he crossed the line to nab the win, Theuns tugged at his jersey to highlight the names on the front in a grateful gesture to the team he's called home since debuting in the top division in 2016.
It hasn't been the smoothest ride for Theuns, who suffered a terrible crash in the stage 13 time trial at the 2016 Tour de France and endured a very long road to recovery. After working his way back to form, he nabbed his first win since the incident – and first ever WorldTour win – at the BinckBank Tour in August. Sunday's victory marks his second career WorldTour victory.
"I am super happy it's my last day riding for Trek-Segafredo, and I am really thankful of the opportunities I have gotten from the team," Theuns said.
"I had a hard period after my crash in the Tour last year, and they always supported me, and I came back, I think, to a higher level. I think there's no better way than to thank the team than with a victory like this."