The Portuguese rider has been racking up consistently strong results in recent years, with a fifth place overall in Volta ao Algarve in February mirroring his 2012 result, and a win in the Klasika Primavera de Amorebieta.
He was then best of the rest behind the Chris Froome/Simon Spilak breakaway on the uphill finish on stage 4 of Tour de Romandie, but it was his defense in the final time trial today which was the biggest morale boost.
"We knew it was certainly hard to be on top of the overall, with Froome the strongest in the mountains and more than a decent time triallist, but there were two podium places up for grabs," Costa said.
"It was sad to lose the chance to be second yesterday with Spilak at the front, but it was a really hard stage and there wasn't any cooperation at all into the pursuit group. Alejandro and I always spoke a lot within ourselves and we were feeling not so well, so we couldn't really get any further yesterday."
Costa was leading RadioShack's Robert Kiserlovski by just one second heading into the time trial, and his teammate Alejandro Valverde was another five seconds back, tied with best young rider Thibaut Pinot (FDJ). Costa was able to post the 12th quickest time in the individual test, and as a result secured third overall by five seconds over Garmin's Tom Danielson.
"I don't know if it's due to the big Portuguese community living here and cheering for me on these roads - the really important thing is that I'm achieving good results in many races. I wasn't really expecting to make it into the best three here, though I gained confidence after doing a good race in Liège."
"This podium was possible thanks to all team members - they committed to us all week and their work was really important. Switzerland keeps bringing me good results. Now I'll be taking a week's rest before starting my build-up to the Tour, with my mind on defending the Tour de Suisse title. That will be probably the only race I'll take part in before the Tour."