"It's encouraging. Bloody hard, but encouraging," Thomas said when he pulled to a stop next to the barriers and snow banks.
He lost ground at two kilometres out and chased solo. At 1,675 metres altitude in Italy's Lazio region, the announcer said "Geraaaiiinnt Thomas" when he finished 18 seconds behind Quintana.
"I didn't really know what to expect," Thomas added.
"The first mountain top of the season. I've been feeling pretty good, so yeah, I'm pretty happy with that."
Thomas began his 2017 season in Australia at the Tour Down Under almost two months ago. He spent two weeks with Chris Froome in South Africa training at altitude.
However, helping Froome win the Tour de France is not his first priority this 2017 season. Thomas will aim for the Giro d'Italia title with Sky co-leader Mikel Landa.
In central Italy, he showed a sample of what fans can expect in the Giro this May 5 to 28. This week, he is up against several of the stars he will face in Giro. Not just Quintana, but the race features Adam Yates (Orica-Scott) – third today at 24 seconds – Tom Dumoulin (Sunweb), Thibaut Pinot (FDJ), Vincenzo Nibali (Bahrain-Merida) and Fabio Aru (Astana).
Sky handled them well today. Michal Kwiatkowski escaped early on the climb and Landa, Diego Rosa, Gianni Moscan and Vasil Kiryienka circled around Thomas.
"It was really good, the team is super strong. I was feeling pretty good. I told Kwiatkowski to have a dig, just to mix it up a bit,” Thomas added.
"Yeah, we had good numbers and that bodes well for the next races."
Thomas fired off with less than five kilometres remaining, drew out Quintana, Yates and Rigoberto Urán (Cannondale-Drapac). Quintana went solo at two kilometres, as he did when he won the Terminillo stage and the eventual Tirreno-Adriatico in 2014, and Thomas chased solo.
"No," Thomas said with a laugh when asked if there was a way to pull back Quintana.
The Colombian toppled Froome to win the Vuelta a España last year, won the 2014 Giro and twice placed behind Froome in the Tour.
"That kick he had, the acceleration is phenomenal and I knew I couldn't match that. I had to kick myself, but just not go well into the red and try to pace it. I started to claw my way back, but he started to kick again, but yeah, not bad."
Sky suffered a major setback in the first day's time trial due to mechanicals and a wheel failure. Thomas as a result sits at eighth at 1-23 minutes.
Thomas, however, won stage two solo and took on Quintana today. It bodes well for the Giro d'Italia, now 55 days away.
"But it's a long way off to the Giro and a lot of guys will get better," he said. "For me it's an unknown, the first time to go for a grand tour, but I think for myself and Landa, we'll have a good chance."
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