Nico Hulkenberg set the fastest time of the morning session of day three in Barcelona as Ferrari completed just four laps.
The Force India driver set the pace with a 1:25.286, leaving him nearly three quarters of a second clear of the rest of the field. It was Hulkenberg's first time in the VJM09 after Alfonso Celis opened the test and Sergio Perez drove on Tuesday, but he was quickly up to speed as he set the pace on medium tyres.
Ferrari had previously topped the times throughout the first two days of testing, with Sebastian Vettel enjoying a strong start to the week. However, Kimi Raikkonen was not so fortunate as a suspected fuel system problem left him confined to the garage for the first three hours of the session.
Raikkonen did finally emerge before lunch but completed just four laps before the chequered flag, leaving him without a lap time so far in the SF16-H.
Kevin Magnussen enjoyed an encouraging return to action on Wednesday morning as he set the second fastest time for Renault. The Dane was dropped by McLaren at the end of last season but will race for the returning French manufacturer in 2016, and 63 laps completed marked more mileage than Jolyon Palmer managed on either of the first two days of the test.
Third fastest was Nico Rosberg - in during the morning session for Lewis Hamilton - with Mercedes again completing the most mileage. Rosberg managed 74 laps and will hand over to Hamilton in the afternoon as the team looks to ensure neither driver has a demanding workload following huge mileage on the opening two days.
Carlos Sainz returned to the Toro Rosso and was fourth quickest, with his lap total of 66 a positive start to the day after a gearbox issue curtailed his running on Monday. Sainz ended the session 0.3s clear of fifth-place Daniil Kvyat, though the Red Bull managed just 29 laps throughout the first four hours.
The top nine cars were all covered by less than 1.7s, with Romain Grosjean ninth on another impressive morning for Haas. The new team managed to get in 54 laps, already 23 more than Grosjean was able to complete on Monday.
Rio Haryanto made his debut for Manor in the MRT05 on Wednesday, though he had to wait over an hour to hit the track. Once circulating, the Indonesian driver was building up confidence in the car until he went off at Turn 5 to bring out the red flags in the final half hour before the lunch break.