While Vincenzo Nibali (Astana) and Alberto Contador (Team Saxo-Tinkoff) consumed vital energy by going on the attack in the final three kilometres, Horner kept his powder dry and did everything he could to stay with eventual stage winner Chris Froome (Team Sky).
He finished fifth on the stage and is now sixth overall, 40 seconds behind new leader Michal Kwiatkowski (Omega Pharma-Quick Step).
"I'm 41 now, so if you don't have it figured out by now then you should've probably retired a long time ago," Horner said laconically as he pulled on some clothing for the descent to the Radioshack team bus.
"I aimed here to be good. This race is the best quality field beside the Tour de France that I've ever seen put together. Paris-Nice: there's nobody there. Everybody's here: the best sprinters, the best GC guys in the world, this is a Tour de France quality field.
"You always want to win and I thought I could get the win but when I saw Froome go I realised that wasn't a possibility.
"I'd be happy with a top 10 in a field of this quality. I'd like to be on the podium now but there's only tomorrow to Chieti that is sharp and steep, I think that this and the TT will decide it, though. My days of the GC were made here."
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Admiration for Team Sky
Horner was full of admiration for how Team Sky and Froome out-rode Nibali and Contador.
"It was intelligent racing from Sky, they have a lot of good guys and Froome was patient. It was a carbon copy of the Tour," he said.
"It's amazing how strong his team was, it was a block headwind and they had two Colombian guys riding on the front. It was just incredibly smart and good racing by Sky. Froome was very patient when Contador was attacking, he stayed with his teammates. They were very strong.
"With one kilometre to go, Contador, Nibali and Santambrogio were gone. But Froome still stayed patient until finally they were in sight, then he just did one acceleration, dropped me and went past the others."
Stephen is one of the most experienced members of the Cyclingnews team, having reported on professional cycling since 1994. Before becoming Editor-at-large, he was Head of News at Cyclingnews. He has previously worked for Shift Active Media, Reuters and Cycling Weekly. He is a member of the Board of the Association Internationale des Journalistes du Cyclisme (AIJC).
