Wirdheim, Leinders, Glock, Zonta and Davidson
Under new regulations for the 2004 season, six of the ten teams (the lower six in last year's championship) are allowed to run a third car in Friday practice. The driver of that car must hold a super license, but must not have participated in more than six Grands Prix in the last two seasons. So who have the teams chosen?
Bjorn Wirdheim, 23, Jaguar:
Wirdheim, last year's FIA Formula 3000 champion, started his motorsport career in karts in his native Sweden. He switched to single-seaters in 1996, winning the Swedish Formula Ford 1600 title the following year. He scored two wins in the German Formula Three series in 2001, as well as taking pole position at the Macau Grand Prix, before moving to F3000 in 2002. He has also previously tested with the BAR and Jordan Formula One teams.
Ricardo Zonta, 27, Toyota:
No stranger to Formula One, Zonta raced for BAR in 1999 and 2000. As a McLaren protege, much was expected of the Brazilian, but in his debut season he was hampered by poor reliability and a heavy crash in his home race, which forced him to miss four rounds. He suffered another two serious accidents in 2000 and lost his BAR seat at the end of the year.
He returned to the sport in 2001 as a Jordan test driver and raced for them twice in place of Heinz-Harald Frentzen, finishing seventh in Canada. However he missed out on a race seat for 2002, and instead returned to competition, winning the World Series by Nissan championship. He became a Toyota test driver in 2003.
Anthony Davidson, 24, BAR:
British driver Davidson has been a Formula One tester with BAR since 2001. In 2002 he also got to race - for Minardi, stepping in for Alex Yoong at the Hungarian and Belgian Grands Prix. He is very familiar with his fellow BAR drivers - he used to race against Jenson Button in karts, and in 2001 he narrowly lost out to Carlin team mate Takuma Sato for the British Formula 3 title. He did, however, win that year's FIA European Cup in F3, taking victories in the prestigious Pau and Spa Masters races.
Timo Glock, 21, Jordan:
Glock, a three-time winner in the 2003 Formula 3 Euro series, only began testing with Jordan earlier this year. The German began his motorsport career in 1997 at the age of 15, winning several karting championships and the BMW Formula ADAC Series in 2000 and 2001. He then finished third in his first International Formula Three Series in Germany in 2002, when he was awarded "Rookie of the Year". In Formula 3 Euro last season he competed against the likes of Jaguar racer Christian Klien and Toyota tester Ryan Briscoe.
Bas Leinders, 28, Minardi:
Belgian Leinders has several titles under his belt, including the European Karting Championship (beating Jarno Trulli) in 1990, the British and European Formula Ford Championships in 1995, the European Formula Opel Championship in 1996 (beating the records of Rubens Barrichello and Mika Hakkinen to obtain eight victories in one season) and the German Formula 3 Championship in 1998. In recent years he has competed in the FIA International F3000 Championship and he finished third in the World Series by Nissan championship in 2002 and 2003. He tested for Jordan earlier this year before signing for Minardi just two days before his first Friday outing for the team in Melbourne.
Sauber have not announced a third driver, having previously suggested that they did not consider running an extra car to be worth the additional expense.