Sagan abandoned both last Sunday's Amstel Gold Race and today's Flèche Wallonne. A team spokesman told Cyclingnews Sagan made the decision at the team hotel after the race, in concert with the Bora-Hansgrohe and his own staff.
Sagan will now have a few more days to relax and recover at home before flying to the US on May 4 to prepare for the upcoming Tour of California.
In a statement sent to media, Sagan laid out his reasons for skipping Liège.
"A hard Fleche Wallonne is over," Sagan's statement begins. "I was there to work for the squad and contribute to the effort to achieve the best result possible. Together with the team, we decided that the best for me now would be to take a few days off in order to better prepare myself for the next races, starting with the Amgen Tour of California on May 12."
Sagan extended his spring season into the Ardennes Classics with the intention of making his debut at Liège-Bastogne-Liège on Sunday. Flèche Wallonne, with its brutally steep clim up the Mur de Huy, was not originally on the cards, however. With a lot of wind predicted for Wednesday, the team decided to bring in the Slovakian to use his crosswinds expertise to guide the team's two leaders through.
It was just his second appearance at Flèche Wallonne after finishing 12th on his debut in 2013. With Movistar pushing a hard pace at the front of the peloton on the penultimate lap of the finishing circuit, Sagan was distanced on the Cote de Cherave.
"It was really fast, really dangerous, we tried our best and I tried to help my teammates. In the end, we did well, fifth and seventh place OK," Sagan told Cyclingnews after coming to the finish in the team car before heading back to the team hotel.
"For sure, I already did a lot before this race, and the day was really hard. I don't think that this kind of final is for me. If I was in my best shape then maybe I could be fifth or 10th, I don't know."
The spring has been hit-and-miss for Sagan, though his best performances have come at the bigger races, such as fourth at Milan-San Remo and fifth at Paris-Roubaix. On his Classics campaign so far, Sagan was pragmatic.
"I think I did a good period when I was always in the front," Sagan told reporters in Ans. "I didn't win, but that's sport, sometimes good, sometimes bad."
Sagan will be hoping to find the good days again in California, where he has racked up 16 stage wins since his first participation in 2010 with Liquigas-Doimo. The rider dubbed 'King of California' by race organisers won the overall at the Tour of California in 2015, and he'll be the headliner again this year, up against the likes of Marcel Kittel (Katusha-Alpecin), Mark Cavendish (Dimension Data), Fabio Jakobsen (Deceuninck-QuickStep), Nacer Bouhani (Cofidis) and Jasper Philipsen (UAE Team Emirates).
After California, Sagan is scheduled for the Hammer Stavanger at the end of May and the Tour de Suisse in June before making a run at another Tour de France green jersey in July.