(CNN) -- Home hero Fernando Alonso set the fastest time in Friday's practice for the European Grand Prix in Valencia -- edging out the Brawns of world championship leader Jenson Button and Rubens Barrichello.
Alonso will be desperate for victory in front of the Spanish fans in Valencia.
Alonso was only cleared to drive on Monday when Formula One chiefs overturned a one-race ban on his Renault team.
The two-time world champion set a best lap of one minute 39.404 seconds over two sessions on the street circuit in the Spanish port city.
But there was a miserable return to Formula One for Ferrari replacement Luca Badoer's who finished 18th best with a lap time over two-and-a-half seconds slower than Alonso's.
Seven-time world champion Michael Schumacher had been due to replace the injured Felipe Massa, but decided against a comeback because of a neck injury.
It was an encouraging return to form for Button, who claimed victory in six of the first seven rounds of the season, but has struggled in recent races.
He now leads Red Bull duo Mark Webber and Sebastian Vettel by 18.5 points and 23 points respectively.
But some improvements in the F1's three-week summer break appear to have helped the Brawn team find renewed pace with Button nearly eight tenths of a second quicker than Webber and just over half-a-second clear of Vettel, who has signed a new contract with Red Bull until the end of the 2011 season..
Defending champion Lewis Hamilton of McLaren, who achieved his first win of the season in Hungary, where Massa was seriously injured in qualifying, was third fastest in the morning session but saw his second stint end after three laps.
Final qualifying on Saturday will determine grid positions for Sunday's 57-lap race.