The 24-year-old American was in pain after spending the day in the breakaway but was proud to have been at the very front of the action on a great day of racing.
King even tried to anticipate Alberto Contador by attacking before the 22 per cent climb to the finish in Guardiagrele. He was passed by both Contador and breakaway companion Simon Geschke (Giant-Shimano) but made it to the top of the climb to finish third at 45 seconds.
"My family is here, all the way from Virginia in the USA, they arrived last night, so it was a special day," he said after getting a hug from his parents and sister.
"It's my first podium finish in a WorldTour race and so I'm pretty happy about that. Having my family here gave me some extra motivation and it was cool to be out front to let them see me on television. I was thinking of a top three or even two. I was trying to get some space from the other guys. I also like to attack, it’s more exciting that way."
King admitted he had been concerned about the 20 per cent gradient of the Muro of Guardiagrele.
"I don’t know if I've ridden a climb like that before in a race. It was so steep. My arms hurt as much as my legs after a climb like that," he said.
"We were talking about it at the breakfast. [David] Millar was already trying to decide the best way to avoid walking up the climb because he didn't want that haunting him all his life. I had that in my mind too and so I wanted to be off the front, so that I wasn't seen walking or running."
King was actually the first rider to hit the climb after getting the green light to go in the breakaway from directeur sportif Charly Wegelius. He then showed the same guts and talent that won him the 2010 US national title.
"On the long climb I couldn't drop Geschke. I attacked him a bunch but I couldn't get ride of him, so we worked together," he explained.
"They gave us a lot of time and when we had 11 minutes I thought we had a chance. Then they started chasing really hard and so we had to start going full gas on the climb."
Then King heard via his radio that Contador was coming across.
"We waited a bit when we heard he was coming across but then he pulled for the last eight kilometres until the climb," he said in admiration.
"We'd done a lot of work but I knew he'd go better than me on the steep part, so I tried to get out front. But I hit the steep part and it was lights out. I honestly thought about getting off and running, it was that steep."