New engine rules should see four drivers who will not race on Sunday providing most of the early action on track in Melbourne.

Step up Spaniard Pedro de la Rosa for McLaren, Toyota's Brazilian Ricardo Zonta, Jordan's Dutchman Robert Doornbos and Red Bull's Italian Vitantonio Liuzzi.

Race drivers must now use the same engines for two successive grand prix weekends, meaning top teams like Schumacher's Ferrari [Images] will restrict their running to a handful of laps on Friday to save the cars for what lies ahead.

"I do not see these new regulations being very conducive to running much on a Friday, save for the third cars which are going to pound around," says McLaren boss Ron Dennis.

"If (McLaren chief operating officer) Martin (Whitmarsh) told me our race cars wouldn't do more than five laps on a Friday afternoon I wouldn't be surprised."

"Our third car will probably crank up as much as 150 laps in the time available and we'll be crawling all over it...if you asked me what are the top four teams going to do, I'd be very surprised if they are doing more than 10 laps."

SPANISH HOPES

Only teams entitled to run a third car in Friday practice -- those that finished last season outside the top four -- will do any significant running with test drivers who have no restrictions on engine mileage.

They include McLaren, who finished fifth last year after their worst championship performance since 1983 but are now tipped as potential champions.

De la Rosa can expect to top the Friday timesheets in at least the first three grands prix while team mates Kimi Raikkonen [Images] and Juan Pablo Montoya [Images] spend much of the day as spectators.

Yet even he is not happy with the situation, despite being handed his first appearance at a grand prix weekend since he raced for Jaguar in 2002, since it prevents him being measured in any meaningful way against his team mates.

"What I would like is to have a Friday free open session for everyone with everyone lapping as much as I will," he told Reuters on Wednesday.

"This is a big opportunity for me. Time is going by and the more years you spend testing the more people forget about you so I must get my act together and get back to racing."

Of the other teams allowed to run a third car, Minardi do not have a reserve driver lined up while Sauber do not have the resources.

Briton Anthony Davidson, the tester who stood out in last year's Friday sessions for BAR, will be absent after helping his Honda-powered team to second place in the championship.

That leaves Toyota, Jordan and Red Bull to join McLaren in giving the crowd something to watch.

"There's nothing that's happening that we didn't predict," said Dennis, who also feels fans will lose out on Sundays with pitstops becoming "incredibly boring" due to new tyre regulations forcing drivers to make one set last the whole race.

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