The Italian, 30, a six times MotoGP champion, used all his experience and guile to keep the challenge from the 22-year-old Lorenzo at bay and leave him in 2nd pacle in front of his home fans. It was Rossi's 99th victory in all categories of motorcycle events..
Six races through the 17-race season, it looks good for Yamaha with Rossi and Lorenzo both on 106 points ahead of Australian Casey Stoner, who came in third on the Ducait Bike in Spain.
Rossi, 30, a six times MotoGP champion, used all his experience to see off the challenge from the 22-year-old Lorenzo and deny him victory in front of his home fans. It was his 99th career victory in all categories.
Andrea Iannone earlier secured a win in the 125cc category when leader Julian Simon strangely celebrated victory a lap too early finishing back in fourth. Obviously a lack of communication in the team, or an inability to count!
While Simon celebrated, Iannone zipped nipped into the lead and Spaniards Nicolas Terol and Sergio Gadea coming in ahead of Simon in second and third place respectively.
Alvaro Bautista of Spain, kept up the pressure on his trailing rivals by winning the 250cc race. This was a second victory in the 2009 season for him ahead of Japan's Hiroshi Aoyama and Hector Barbera from Spain in second and third respectively.
In an exciting last lap duel, world champion Valentino Rossi won a thrilling Catalan MotoGP grand prix pipping his Yamaha Motorcycle team mate Jorge Loenzo on the final corner to pick up his second win of the 2009 season.
Spaniard Lorenzo started in pole position with Rossi in second. The team mates changed the lead several times during the race at a very warm Circuit de Catalunya in Barcelona. On the last lap, Rossi timed his final charge perfectly to pass his Spanish and take the chequered flag.
