BMW's Colin Turkington asserts his authority at the head of the BTCC field by setting the pace in Crofts first practice of the day.

The championship leader wasted no time in sending an ominous signal to the rest of his title rivals and set a 1 minute 24.498 around the Croft circuit, putting himself over half a second ahead of his nearest challenger Andrew Jordan in second position despite carrying full success ballast.

After recently seeing his promising early season pace slip away, Mercedes' Adam Morgan propelled his Cicely-run A-Class back into the top three but even he was over a second off Turkington's ultimate pace.

Fourth and the second eBay Motors BMW was Nick Foster, who follows on from his fine Oulton Park performance. Foster headed both of the factory MG's of Jason Plato and Sam Tordoff in fifth and sixth.

Glynn Gleddie displayed the impressive development of his United Autosport outfit as the Scot ended the first practice session seventh in his Toyota Avensis.

Speeworks' Tom Ingram maintained his consistent approach in eighth as the BTCC rookie led the legend pairing of Honda's Matt Neal and VW's Alain Menu to complete the top ten order.

Oulton Park's popular race three winner Aron Smith made a steady start to the weekend in 14th while Turkington's main title threat, Gordon Shedden, followed the VW in 15th.