As the 2010 pre-season winds down on Sunday, F1's pecking order for the forthcoming world championship continued to develop.
On the final overcast morning of the Barcelona test, many runners took fuel out of their cars and fitted new tyres to gauge raw qualifying pace.
McLaren's Lewis Hamilton went into the mandatory lunch break with the quickest time of the entire test, having already said the MP4-25 is "light years" better than its predecessor.
Driving the same upgrade as had Jenson Button a day earlier, it is believed Hamilton has a better grasp of the silver car than the reigning world champion.
"I'm reasonably happy with it," Button said on Friday after testing the new front wing, diffuser, engine cover and exhausts.
"There's more to come," he added, having set a time a full second behind Hamilton's Sunday morning best.
Also quick on Sunday morning were Ferrari's Felipe Massa, Red Bull's Sebastian Vettel and Michael Schumacher in the Mercedes, encapsulating the belief that all four teams are a step ahead of their next rivals.
But worryingly for all of his and teammate Fernando Alonso's competitors, Massa said the latest package put together for the F10 gives the Ferrari "more grip and more downforce".
"It's encouraging, because it means that we made another step ahead compared to Jerez," said the Brazilian.
Next best was Williams' Rubens Barrichello, and he told reporters in Spain that he thinks his new British employer "can be one of the teams to surprise people this year".
Button said late on Saturday that Sauber could also be a surprise of 2010, before the Swiss team's Kamui Kobayashi slotted between Toro Rosso's Sebastien Buemi and Force India's Adrian Sutil on the Sunday morning timesheet.
Robert Kubica had just the ninth quickest time in the Renault, comfortably ahead of the two new teams Lotus and Virgin.
The Pole admitted the R30 car is not a podium contender.
"We have to be realistic, so we will not go to Bahrain to fight for the podium, that's for sure," he said.
Heikki Kovalainen was at the wheel of the Lotus for the final day of winter testing, after his teammate Jarno Trulli said the T127 is "probably four seconds off" the pace of the leaders.
