After a subdued Spa showing, Lewis Hamilton underlined the threat posed by McLaren at this weekend's Italian Grand Prix, as he and team-mate Heikki Kovalainen led the way in opening practice at Monza.
On a circuit expected to favour the KERS-equipped cars, Hamilton set at the top of the times for much of the 90-minute session, eventually leading the way by nearly four-tenths of a second as he set the weekend's first benchmark at 1min 23.936secs. The Briton was the only driver to break into the 1min 23s, with Kovalainen next up on 1min 24.332secs on an otherwise uneventful morning.
With the ten teams all following their own pre-prescribed programmes, direct comparison between the KERS teams, and between the KERS cars and their less well-spec'd rivals, would have to wait for a later time, with McLaren's main expected opposition, Ferrari, a little way down the order. After languishing at a Luca Badoer-inspiring 19th for some time, the Scuderia's newest signing, Giancarlo Fisichella, vaulted into eighth spot as the session drew to a close, while Belgian GP winner Kimi Raikkonen was a couple of spots further back, the pair clocking 1min 24.732secs and mi 24.761secs respectively.
Although Renault's Fernando Alonso claimed fourth place in his re-KERS'd R29, a further tenth and a bit shy of Hamilton, the remainder of the top ten was populated by a broad selection of teams, with Adrian Sutil's Force India keeping up the team's strong form after Fisichella's second at Spa in third place.
Nick Heidfeld was fifth for BMW Sauber, ahead of the surprising Sebastien Buemi - reprising predecessor Sebastian Vettel's front-running role from 2008 for Toro Rosso - Jenson Button and Mark Webber claiming the remaining spots in the top half of the table.
Webber's Red Bull team-mate, and 2008 Italian GP winner, Vettel was only 18th after limiting himself to just eight laps in order to protect his fragile engine count after arriving at Monza with just one new unit remaining in his allocation. Vitantonio Liuzzi was 16th on his return to action as Fisichella's replacement at Force India, while Toyota twins Jarno Trulli and Timo Glock brought up the rear as the TF109 again showed its dislike of kerbs. The German was the only driver to spin during the session.