Laser Tools Racing's Aiden Moffat has emerged from the opening British Touring Car Championship practice session quickest of all after beating Andrew Jordan's time late in the session at Croft.
Jordan had led most of the 40-minute running after taking over the reigns from Subaru's Colin Turkington but a late charge up the order from the Mercedes A-Class driver saw Moffat pip the Motorbase Ford Focus by 0.026s.
Despite running a full 75 kilos of success ballast - as virtue of leading the title chase - West Surrey Racing's Sam Tordoff was next to arrive in the timesheets with the third quickest effort.
A productive series of laps throughout the mid-part of the session elevated Tordoff up into the top two before Moffat lowered the benchmark with a 1 minute 25.038 second lap.
Tordoff's lap was just 0.010s ahead of Speedworks Motorsport's Tom Ingram in fifth while Adam Morgan ensured both Mercedes A-Class machines finished FP1 firmly in the top five after producing the fifth fastest effort.
Championship leader Tordoff was the only BMW runner to make the top-ten at this early stage of the weekend.
Silverline Subaru BMR Racing's Turkington eventually fell to sixth by the session end but remained ahead of Honda's Gordon Shedden and BKR's Aron Smith, who trailed the Levorg in seventh and eighth.
Turkington's lap in sixth meant just 0.154s covered the top-six runner while the entire top-twelve was separated by little under 0.5s.
Eurotech Racing completed the remainder of the top-ten with Martin Depper getting the better of his younger rookie team mate Daniel Lloyd right at the death of the session.