Raikkonen fastest as McLaren woes continue

Kimi Raikkonen's Ferrari posted the fastest time on the fourth and final morning of the first pre-season Formula One test in Barcelona on Thursday as McLaren-Honda were hit by more reliability problems.

Raikkonen posted the third fastest time of the week of 1min 23.477 on the new ultrasoft tyres, but was over six tenths of a second down on the time set by team-mate Sebastian Vettel on the same setup on Tuesday.

Fernando Alonso managed only three installation laps for McLaren as their problems continued after a hydraulic issue curtailed Jenson Button's second day in the MP4-31 on Wednesday.

However, Honda confirmed they are hopeful the two-time world champion will be able to run in the afternoon.

"@Alo_Oficial (Alonso) will be back behind the wheel of the #MP431 later today," they posted on their official Twitter account.

A former McLaren man Kevin Magnussen enjoyed an encouraging morning for Renault on their return to the sport as a constructor with the second fastest time and 67 laps.

With the rest of the field prioritising testing reliability over speed, Max Verstappen was third fastest in a Toro Rosso.

Mercedes again piled on the laps as world champion Lewis Hamilton racked up 97 before handing over driving duties to Nico Rosberg for the afternoon down in sixth fastest.

The German giants also caused a stir by debuting a new nose to the W07 which could give the runaway leaders in the past two drivers' and constructors' championships an even more commanding advantage in 2016.