Fernando Alonso delivered the perfect response to Red Bull Racing's early pace-setting form in the final pre-season test, when he dominated the second morning's running at Barcelona on Friday.
After a frustrating opening day to the test, where he had lost track time through an electrical problem, Alonso spent the second morning working on qualifying simulations to better Webber's time by a considerable margin.
With his F10 fitted with a raft of aerodynamic upgrades for this week's test, Alonso made good use of a more-rubbered in track to pull off a sequence of quick laps early on - despite one brief trip across a gravel trap at Turn 10.
His best effort of 1m20.637s came on the first lap of his fifth short run, before his programme switched to a longer stint before the lunch break. He is expected to focus on a race simulation in the afternoon.
Alonso's fastest time compares with Webber's best effort from the opening day of 1m21.487 - when the track was still very dirty - although it is not clear how the fuel loads of the Ferrari or Red Bull Racing car compare.
Behind Alonso, several other drivers worked through qualifying simulations as they make their final preparations for the season-opening Bahrain Grand Prix.
And it was BMW Sauber's Pedro de la Rosa who emerged as Alonso's nearest challenger, with the C29 maintaining the impressive form it has shown in early testing.
The Spaniard set his best effort of 1m20.973s shortly before the lunch break, to just edge out Vitantonio Liuzzi in the Force India.
Sebastian Vettel managed to better team-mate Webber's best time from the first day of the test with a lap of 1m21.258s as his morning's programme seemed to mirror what Red Bull Racing did on Thursday.
He completed a series of short qualifying-type runs, with his best lap coming in the final effort before the lunch break.
Jaime Alguersuari was fifth fastest, with Toro Rosso completing a series of short runs in the morning - prior to a bit of pitstop practice before the lunch break. The Spaniard is set for a race simulation run in the afternoon.
Michael Schumacher and Lewis Hamilton ended the morning session in sixth and seventh place on the timesheets, as they worked through various programmes - which included pitstop work and some long runs.
The busiest man of the morning was Nico Hulkenberg, who completed a total of 82 laps in his Williams. The German did some short runs early on before moving on to a race simulation run. He ran a 19 lap stint before a pit-stop for new tyres, and then added a further 27 laps before the chequered flag brought a halt to proceedings.
Hulkenberg's fastest lap of 1m23.513 came right at the end of that second long stint.
Behind ninth fastest Robert Kubica, Timo Glock completed 14 laps for Virgin Racing as the team returned to the track for the first time since Lucas di Grassi's crash on Thursday.
Jarno Trulli was the slowest driver, having lost time in the morning with a seat problem before completing 35 laps for Lotus.
Pos Driver Team Time Laps
1. Alonso Ferrari (B) 1:20.637 60
2. de la Rosa BMW-Sauber (B) 1:20.973 46
3. Liuzzi Force India-Mercedes (B) 1:21.056 23
4. Vettel Red Bull-Renault (B) 1:21.258 55
5. Alguersuari Toro Rosso-Ferrari (B) 1:21.571 36
6. M.Schumacher Mercedes GP (B) 1:21.689 45
7. Hamilton McLaren-Mercedes (B) 1:22.152 39
8. Hulkenberg Williams-Cosworth (B) 1:23.513 82
9. Kubica Renault (B) 1:24.912 44
10. Glock Virgin-Cosworth (B) 1:26.622 18
11. Trulli Lotus-Cosworth (B) 1:26.677 40
All Timing Unofficial
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