Lewis Hamilton says he has yet to fully exploit the potential of the Mercedes W07 so far this season.
Nico Rosberg has won the opening four races of the season, with Hamilton hampered by a poor start in Australia and suffering contact with Valtteri Bottas at Turn 1 in Bahrain having been started from pole position on both occasions. Reliability issues then struck in China and Russia, but Hamilton says he has been happy with the car when he has had a trouble-free session.
"It's been good to have a break after Russia," Hamilton said. "Over time you reflect on each race weekend and what you might have done differently, so you can learn from each experience and move on.
"I'm really proud of the guys in the garage: we've had a hard time but they're doing a fantastic job and I'm really happy with how we've been working together. Every weekend, we've got the car into a great place setup-wise - I just haven't been fully able to exploit it. So the glass is half full for me."
And Hamilton has praised the reaction from Mercedes to his MGU-H problems in Russia, which Paddy Lowe says has been the "highest priority" for the team ahead of the Spanish Grand Prix.
"It will be a big challenge but there's a long way to go with 17 races left and, if the last four are anything to go by, there's a lot more still to come from us. The team has been on it 24/7 since returning from Russia so I'm confident they'll get to the bottom of the problems we've been having.
"I know I'm still quick. I've known that since day one in testing and, when I've had clean air and a damage-free car this season, I've shown it on track. I head to Spain confident of a good weekend."
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