The BMC team leader survived a tense day in the saddle on stage 3, which went to Koen Bouwman of Lotto Soudal out of the day-long break as Thomas De Gendt (Lotto Soudal) retained his overall lead.
“Today felt like a stage of the Tour de France," Porte said after the stage. "It was so stressful the entire day.
"I think the guys did a really good job again in keeping me out of harm's way because there were a few times there that I almost found myself on the deck.
"It was such a sketchy day and I’m really lucky to get through it unscathed. It’s a silly thing to say but really the race begins tomorrow.”
That "tomorrow" is a time trial that is perhaps not specifically suited to his talents, Katusha-Alpecin's Tony Martin is the favourite for the stage, but Porte will hope to place himself in a good position relative to his rivals ahead of the decisive mountain stages to come.
“We’ve already had a look at the time trial course," he said. "I don’t think it’s the best course for me but at the end of the day, you deal with what you’re given.
"I think if I have a good day, maybe I can take some good positions on GC.
"It’s the same sort of length to the final Tour de France time trial in Marseille. I haven’t seen that one yet, but I think tomorrow’s time trial is hard enough that someone who can climb but still hold the power on the downhill and flat can win the stage.”
With a 1min 9sec lead on the GC favourites, De Gendt will hope to stem the tide and hang on to yellow for another day but even he agrees it will be a close battle to stay ahead of the likes of Porte, Chris Froome (Sky), Alberto Contador (Trek-Segafredo) and Alejandro Valverde (Movistar).
"I'm happy that I retain the yellow-blue jersey again. It was my goal to reach the time trial in this position," De Gendt said. "I hope I can stay in the lead again tomorrow. Sometimes I can do a good time trial, sometimes it's the complete opposite.
"I have just over one minute margin onto the GC favorites. It will be close. I'll keep the jersey or I'll lose it by a few seconds but I'll give my best."