Barcelona, Day Two: Sergio Perez shows MP4-28 speed as Red Bull hit problems
Mercedes also show promise but unreliability for World Champions and Lotus
By James Galloway and Mike Wise in Barcelona
Last Updated: 20/02/13 9:12pm
For the second successive day, testing at the Circuit de Catalunya was dominated by the grid's established front-running teams, with last year's top five Constructors' Championship finishers disputing the top five positions on the Day Two timesheet.
The one big difference from Day One, however, was the arrival of McLaren at the sharp end of proceedings as Perez, on his second and final day in the MP4-28 this week, became the first man this year to dip below the 1:22 barrier - the Mexican's impressive lap of 1:21.848 coming on a single-flying lap run on soft tyres.
That mid-afternoon effort took Perez three tenths of a second clear of Sebastian Vettel, whose earlier 1:22.197 time had come on the first of three laps on the soft tyre. However, Red Bull's day soon ran into trouble thanks to what the World Champion would later describe as "small things".
Up until that point Red Bull, having completed pitstop practice with their new traffic light system in the morning, had appeared to be gearing up for their first full race simulation of the winter as the team's hierachy all took up their usual positions on the pit wall.
Vettel initially completed 28 laps across stints on the soft and hard tyre, before returning to the garage for a lengthy spell after the team identified a loss of pressure, before resuming the programme on Pirelli's harder compound once more.
However, following a pitstop with 45 minutes of the session remaining, the German's RB9 ground to a halt on the exit of the pit lane and the car was soon being returned to the team on the back of a truck.
Although Vettel was forced to sit out the rest of the session, Lotus rival Kimi Raikkonen had been cast into the role of spectator for most of the morning after the team ran into gearbox problems on the E21.
Coming in wake of telemetry glitches on Tuesday, such a lengthy change was hardly what the team needed, yet once back on circuit, Raikkonen was swiftly into the top three with a medium-tyred lap of 1:22.697.
That inched him ahead of Mercedes' Lewis Hamilton, but the Brackley team's up and down winter hit one of its higher points on Day Two as the returning Briton racked up more laps than anyone (121) across the session.
And while he technically finished 0.8s off the pace of his old team, Hamilton's 1:22.726 effort was noteworthy because it came on the hardest, and theoretically slowest, Pirelli tyre available.
Indeed, the former World Champion had earlier caught the attention by setting his fastest lap of another competitive hard-tyre stint on his second timed run, something most drivers have been struggling to do due to high degradation levels.
Mercedes, along with McLaren, were the only leading teams to avoid delays with reliability concerns also affecting Ferrari as a problem with an exhaust pipe restricted Fernando Alonso to just 76 laps.
His fifth-fastest time was set on the medium compound.
Valtteri Bottas got his first taste of the new Williams and the FW35's immediately impressive reliability allowed him to all-but reach a century of laps, the Finnish rookie outpacing Toro Rosso's Daniel Ricciardo and Force India's Paul di Resta to claim sixth place.
"I had a really strong first impression of the FW35 today," remarked a happy Bottas. "Straight out of the box I knew we had made a step forward from last year."
Sauber, meanwhile, became the latest team to run a rear-wing stalling device - or passive double DRS - on their C32 as Nico Hulkenberg completed plenty of laps (88) without setting the timesheet alight. The German largely focused on aero, tyre and set-up work.
Marussia's Max Chilton brought out the day's only other red flag when he stopped in the closing minutes of the session between Turns 12 and 13 in a planned fuel stoppage. Like Hulkenberg, the British rookie had spent much of the day focusing on specific items but prior to stopping did move ahead of Caterham's Charles Pic with his fastest lap of the test.
Barcelona Day Two Timesheet
1. Sergio Perez, McLaren, 1:21.848, 97 laps (Soft tyres).
2. Sebastian Vettel, Red Bull, 1:22.197, 84 laps (Soft tyres).
3. Kimi Raikkonen, Lotus, 1:22.697, 43 laps (Medium tyres).
4. Lewis Hamilton, Mercedes, 1:22.726, 121 laps (Hard tyres).
5. Fernando Alonso, Ferrari, 1:23.247, 76 laps (Medium tyres).
6. Valtteri Bottas, Williams, 1:23.561, 98 laps (Soft tyres).
7. Daniel Ricciardo, Toro Rosso, 1:23.718, 70 laps (Medium tyres).
8. Paul di Resta, Force India, 1:23.971, 62 laps (Medium tyres).
9. Nico Hulkenberg, Sauber, 1:24.205, 88 laps (Medium tyres).
10. Max Chilton, Marussia, 1:25.115, 67 laps.
11. Charles Pic, Caterham, 1:26.243, 102 laps.