Lopez is convinced that Raikkonen dug deep to get the best out of himself, even though from the outside it was not always obvious.
"Everyone who had muttered that he wasn't motivated now comes around to tell me they knew Kimi was still super strong," said Lopez in an interview with Gazzetta dello Sport.
"It amuses me. I knew it would have ended up this way. Raikkonen has added hard work to his talent, and the results are the fruits of this cocktail."
When asked if Raikkonen was doing so well simply because of the freedom Lotus had given him, Lopez said: "It's not just the freedom. Raikkonen in Lotus feels utilised for what's most important, while he is free for everything else. He has found balance.
"Keep him under control? Not even in my dreams. I talk to him every week and he feels good, he is enthusiastic and charged up. I want drivers, not robots."
Lopez has also expressed his full support for Romain Grosjean, whom he reckons was unfairly criticised at times because of his involvement in a number of early race accidents.
"Romain didn't do all the mess he's been accused of," he said. "They [the critics] exaggerated on his account: in 2012 there were four drivers who were reprimanded more often than he was, however they were able to take part in every race.
"Grosjean instead was banned for the Italian GP. He paid for many others. But he has always shown he is quick. I expect a lot of him this year."