Jorge Lorenzo says Valentino Rossi's move to Ducati gives him and Yamaha "great motivation" to beat his current team-mate in 2011.
Rossi has signed a two-year deal with the Italian manufacturer and Lorenzo is eager to show that he can defeat the seven-time MotoGP world champion.
"Yamaha will do its maximum to beat him; more speed and engine power will be needed but we will work harder than ever," said Lorenzo. "Next season will be a very interesting championship."
The Spaniard has shared a difficult relationship with Rossi as team-mates, with a wall separating the riders in the Yamaha garage.
"I didn't like the wall," Lorenzo said. "I would have expected more of Rossi from the human side, rather than a bigger exchange of technical information. He unintentionally made me a favour, however, because he has made my team even closer together, and I now go even better since I don't have access to his telemetry.
"I've never felt nervous about the idea of fighting against Rossi. I knew I had to learn, improve and work hard. I've watched the races on TV since I was 10 and have learnt something from riders in every class. From Valentino I've learnt how to manage the race on and off the track much better."
Rossi will be replaced at the factory Yamaha team by current Tech 3 rider Ben Spies next year, and Lorenzo predicts that his relationship with the American will be less volatile.
"I can feel we will have a good relationship with Ben," he said. "Perhaps we won't be best friends, but there won't be a wall in the garage and we won't keep our telemetries secret."