Paolo Bettini (Quick Step) lived up to his world champion?s status in California on Thursday, winning the 132-mile fourth stage along the breathtaking Pacific Highway to San Luis Obispo with an impressive sprint.

The pocket-rocket Tuscan was up against all the powerful sprinters in the US race but used his clever riding and acceleration to beat them all and take his first victory of the 2007. It took close scrutiny of the photo finish to decide the winner but Bettini knew he had beaten Gerald Ciolek (T-Mobile) and JJ Haedo (CSC).

Levi Leipheimer finished in the bunch and so kept his three-second overall race lead on Jens Voigt (CSC). Australia?s Rory Sutherland (Healthnet) is third at 15 seconds. Overall victory in the race is expected to be decided in Friday?s 14.5-mile time trial, with a Leipheimer against Voigt battle expected.

Bettini was all smiles after taking his first win of the season.

?It was a tough stage but I?m very happy to have won. It?s my first time in California and I?ve won a stage, that?s good for me and for the team,? Bettini said.

?It?s an important win for me. It?s a great experience just to race in America, to win a stage is even better. The public is incredible in America. They?re more enthusiastic than in Italy or in Europe. The race isn?t over yet and when I start winning I like it even more.?

?The finish was a little bit difficult and dangerous but some other riders had explained the finish to me and so I was careful to take the last corner in the first six places. I only won by a bit but I won and that?s the most important thing.?

Leipheimer carefully protected his race lead and was clearly thinking about Friday?s time trial.

?The weather wasn?t so bad. It was grim when we woke up but it cleared up and we only rode through one shower but it was short. It was the postcard stage of Tour of California. It was pretty beautiful out there. Fortunately it went smoothly for us. The team worked well but I think the guys in the bunch were tired from yesterday?s stage.?

?I?m pretty confident for the time trial. I feel good and think I?m the best rider in race. I prepared well and trained hard this winter. Jens is a tough competitor and he?s beaten me in the past but I?m going to give it everything tomorrow.?

?I?m fairly familiar with the course. I did it three times during our training camp in Solvang. I did it on my time trial bike and did sections pretty hard so I know what it feels like to go hard on course. It doesn?t seem fast, it?s a tough course and so there will be decent gaps. It?s not as big as last year?s course but I can?t judge what the gaps will be. I?ll go as hard as I can and I?ll have the advantage of starting last and that will help me a lot.?