First, the Deceuninck-Quick Step rider dropped his breakaway companions with 75km to race on the 207km stage from Stockton to win solo in Morgan Hill, the home of bike sponsor, Specialized.
However, getting there for Frenchman became an adventure as he struggled with some hairy moments on the descents in a determined effort to hold off the chasers, in particular, Team USA's Alex Hoehn.
“Since winning last year in Belgium, I was in search of another victory, and taking it today gives me huge satisfaction," Cavagna said. "I came in California to help the squad, to pull in the bunch every day, but the team gave me freedom today and I am happy I could repay them for their confidence.
"In cycling, you need to take your chance and give your best every single time, because sometimes it works. This was the case for me today."
Cavagna demonstrated his courage in giving everything he had to finish it off but the 23-year-old clearly needs some work going downhill with his lines on the numerous hairpins leaving a lot to be desired for a rider on a WorldTour team.
“The stage was so long and hard. We rode full gas from the start, and when I sensed there was an opportunity, I jumped into the breakaway, where we worked really well together," Cavagna said.
"Then, when I attacked, I felt I could go all the way. Ok, I was a bit scared on the downhill, because it was a very difficult one, but I remained calm and went as fast as I could there.”
In the end, he survived hid descending demons to win by over seven minutes ahead of Ben King (Dimension Data) and Simon Geschke (CCC Team).
The bunch sprint was won by Cavagna's Deceuninck-Quick Step team-mate Kasper Asgreen while overall leader Tejay van Garderen (EF Education First) sat in the pocket of his team to retain his position.
Stage 4 takes the peloton 212km from the Laguna Seca Raceway to Morro Bay, a course designed for the sprinters.