Ivory Coast international Drogba moved to Shanghai Shenhua this summer, leaving a hole which Mata's fellow Spain international Fernando Torres has struggled to fill.
In an interview with French magazine So Foot, Mata said: "Drogba's departure was like an electric shock for us. He was a warrior.
"We've had to learn to cope without him because for many long years he was Chelsea's lightning conductor.
"With Drogba we were conditioned to play in a certain way."
Torres has faced much criticism for his performances, but Mata believes the onus is on his team-mates to adapt to the former Liverpool player's style.
"His runs aren't the same," said Mata. "He's not a funnel for our play like Drogba could be.
"He doesn't like the holding-it-up role. He prefers finding space and facing the goal."
Despite his struggles since moving to Stamford Bridge, Mata still has full confidence in Torres.
"For me, he is still one of the best strikers in the world," he said.
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