Van Emden, who recently won Dwars door West-Vlaanderen in Belgium, started the 10km test in San Benedetto del Tronto less than halfway through 159-rider field and set the early fastest mark at 11:21. The 32-year-old Dutchman waited nearly two hours in the hot seat before Rohan Dennis, who started third from last, crossed the line three seconds faster to take the lead and eventually the stage win.
It was a heartbreaking loss for van Emden,
"When you're so close, you just want to win," he said. "I'm very disappointed."
Van Emden also lost the Eneco Tour time trial last year to Dennis.
"It's the second time that I've missed a WorldTour victory because Dennis is faster," he said.
The last-second loss for van Emden is similar to his 2015 runner-up result in the weather-shortened Tour of California time trial, where he set the fastest early time and then waited patiently in the hot seat before Peter Sagan, who started second to last as the overall runner-up, beat his time by 15 seconds to take the stage win.
Van Emden's result was one of two top-five finishes for the Dutch team after Primož Roglič preserved his fourth-plcae overall position with a top five ride on Tuesday, covering the course 11 seconds behind Dennis.
"I looked forward to this stage," Roglič said. "Every day I have to work hard for the GC, but today, I was focussed on the stage win. My main goal in such a time trial is to race 10 kilometres as hard as I can. I did it today."
Jungels rides time trial into Tirreno's white jersey
The 24-year-old started the day 16th overall, 16 seconds behind youth classification leader Egan Arley Bernal (Androni Giocattoli-Sidermec) in 15th.
Jungels trailed the Colombian at the intermediate checkpoint of the 10.1km out-and-back time trial, but a strong showing in the second half lifted him past Bernal by 43 seconds and into the lead of the youth classification.
Jungels also passed Michael Scarponi (Astana) in the general classification, moving into 14th overall.
"It's been a tough race," Jungels said. "I can't say I am 100 per cent satisfied with my time trial, but I'm happy to be back on track after crashing on the second stage. Tirreno-Adriatico is an important race, a World Tour event, and to be on the podium and don the white jersey again gives me joy.
Jungels is now pointed toward the Giro d'Italia, where he won the youth classification last year in his first attempt at the Italian Grand Tour.
"This is where my preparation for the Giro d'Italia starts," he said on Tuesday. "I've been working hard during the winter, I like Italy and I hope to continue my good results here in May."
AG2R La Mondiale backing Bakelants in Milan-San Remo
Jan Bakelants will lead an eight-man AG2R La Mondiale roster at Milan-San Remo that got a last-minute shake up after Matteo Montaguti fractured a rib Sunday in a crash at Tirreno-Adriatico that forced him to abandon the Italian WorldTour race.
In Montaguti's absence, 22-year-old Quentin Jauregui will get his first ride in a Classic since he rode Paris-Roubaix and Tour of Flanders in 2015. This year will be Jauregui's first attempt at La Primavera.
"Milan-San Remo was not on my program," the young Frenchman said. "When I was told that I would be replacing Matteo Montaguti, I was both happy and a little awed. It is a monument, seven hours in the saddle, and only champions have a chance in the final. I am very happy to have the opportunity to discover this race."
Jauregui last raced in Strade-Bianche, where he finished an impressive 12th, 4:05 behind winner Michal Kwiatkowski (Team Sky).
"After Strade-Bianche I lightened up on my training program and have returned to work this week, including a six-hour ride on Tuesday in order to be ready to support Jan Bakelants," Jauregui said. "My form is good. I raced at the front for the Strade-Bianche, which is a fabulous race, and managed a reasonably good place at the finish. Then I will move on to work for Romain Bardet in Pais Vasco."
AG2R La Mondiale for Milan-San Remo: Gediminas Bagdonas, Jan Bakelants, Nico Denz, Mathias Frank, Alexis Gougeard, Hugo Houle, Quentin Jauregui, Stijn Vandenbergh.
Tirreno-Adriatico stage 7 highlights - Video
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