Scuderia Toro Rosso's debut of the STR3 went swimmingly Wednesday in Barcelona, Spain, until the team's rookie driver Sebastien Bourdais scraped off the left side of the car after entering Turn Nine of the Circuit de Catalunya with a bit extra gusto. The write-off will prevent further testing of the car expected to race in Turkey in May.

He later said the car worked well and was an improvement upon its predecessor.

Bourdais's excitement overshadowed a fast time by Renault's Fernando Alonso, who topped unofficial time charts with a fast lap of 1 minute, 18.483 seconds. As have fast-lap runners before him this test week, he used slick tires in a preview of rules changes for 2009. The week's only other lap times in the 1:18s, by Brazilians Felipe Massa and Rubens Barrichello, have been on slicks. Michael Schumacher, testing Bridgestone's grooveless tires for Ferrari, could not drop below 1:19. His 1:19.323, in an F2008 adjusted to '09 specifications, was second-quick.

"The day has been good and I was happy with the developments to the car," Alonso said. "We still need to keep improving because our competitors have also improved. It's difficult to say how we really compared with them."

Alonso called the slick tires "fun" and said "they gave very good grip."

Force India's Adrian Sutil came third-quickest at 1:19.424, followed by BMW Sauber's Robert Kubica at 1:19.785, Williams's Nico Rosberg at 1:19.841, Honda's Barrichello at 1:19.920, McLaren Mercedes's Lewis Hamilton at 1:20.591, Bourdais at 1:20.715, Red Bull's Mark Webber at 1:20.849 and Toyota's Jarno Trulli at 1:20.867.

Barrichello completed the most laps, 141, and Rosberg the fewest, 65, after a mechanical gremlin kept him off track early in the day. Sutil completed 102 laps despite suffering a clutch problem.

"It was the first time I'd tried slicks this year and I was really impressed," Sutil said. "The grip is amazing but it's also very physical on your neck muscles."

Hamilton, Webber, Trulli and Bourdais stayed on grooved tires throughout the day.

Kubica smacked a barrier, late in the day, as a result of an undisclosed technical problem. The shunt damaged suspension and front wing.

Working in spring conditions in which morning overcast gave way to sun and breezes, teams again split time between setup work for the race on this circuit at the end of the month and testing development for 2009.