Romain Grosjean again topped the times for Lotus on the third and final day of the Formula One in-season test at Mugello, while Ferrari unveiled major revisions to their 2012 challenger.

Grosjean, along with Sauber's Kamui Kobayashi, had been the quickest of the runners in Wednesday's running.

And he repeated the feat with a time of one minute 21.035 seconds during today's afternoon session, which ended up being the fastest recorded by anyone over the three days as Lotus underlined the form that saw them claim a double podium in Bahrain.

World champion Sebastian Vettel was second fastest for Red Bull, setting his best time during the morning running to finish just a tenth ahead of Fernando Alonso.

Ferrari chose the final day to try out upgrades to the design of the rear bodywork and exhaust on the F2012, after a disappointing start to the season.

Alonso wasted little time in getting down to business, posting a time of 1min 21.363secs to top the timesheets early in the day.

But the Spaniard's progress was hampered when he had an off at turn 12 and put the car nose first into the barriers, bringing out one of several red flags and costing him two hours of track time.

Toro Rosso's Daniel Ricciardo joined the top three in the 1:21 bracket, with the Sauber of Sergio Perez over half-a-second further back in fifth place.

Nico Hulkenberg was sixth for Force India, but his team-mate Paul di Resta could only manage 10th quickest time after experiencing more technical problems this morning to go with the hydraulic woes that severely curtailed his running yesterday.

Pastor Maldonado was seventh for Williams ahead of the Mercedes of Chinese Grand Prix winner Nico Rosberg.

Oliver Turvey was ninth for McLaren as the Woking-based team finished a low-key workout in Italy, with Di Resta rounding out the top 10.

Caterham's Heikki Kovalainen, who completed the most laps on the day with 139, and Marussia's Timo Glock were the last of the runners in 11th and 12th.

Reflecting on another positive day, as Lotus worked on suspension configurations and some floor updates, Grosjean said: "We made a big change to the car at lunchtime and everything went according to plan.

"We were conducting a specific programme of evaluating components, so to be quick relative to our opposition even when we were not looking specifically to try to top the times is satisfying.

"I'm looking forward to seeing how well this translates into lap time when we get to Barcelona.