Team BMR Subaru racer Ash Sutton starred at Croft, taking a victory and two runner-up positions as he moved within 20 points of the British Touring Car Championship (BTCC) lead.
However, the event was overshdowed by a qualifying crash that left three drivers with serious injuries.
Triple Eight MG Racing’s Aron Taylor-Smith (MG 6), Motorbase Performance’s Luke Davenport (Ford Focus) and Eurotech Racing's Jeff Smith (Honda Civic Type R) were all hospitalised in the incident at Barcroft corner; Taylor-Smith was released later that day with a fracture to his foot, but the other two drivers remain in hospital with injuries that are described as "not immediately life-threatening".
Smith is described as being in a "serious but stable condition", with multiple chest injuries, extensive shoulder injuries, a broken left arm and concussion. Davenport has been placed in an induced coma with multiple chest injuries, lung damage, a broken right leg, broken pelvis, broken right arm and concussion. His condition is also listed as "serious but stable".
BTCC Croft - round 13
Ash Sutton (Subaru Levorg) took his second victory of the season from pole position in the opening 15-lap race.
His victory was hard-earned, however, as he held off the WSR BMW 125i M Sport of Colin Turkington throughout, crossing the finish line just 0.6s ahead of his rival.
Behind, Mat Jackson (Motorbase Ford Focus) ensured the top three qualifiers finished in that order - in stark contrast to fourth-placed Rob Collard. The WSR 125i M Sport racer climbed from 11th on the grid to fourth place, despite running with significant success ballast.
Probably Collard’s best move came when he nipped past reigning champion Gordon Shedden (Team Dynamics Honda Civic Type R) on the final corner, the Scot leaving enough room as he was mindful sixth would be enough to maintain his championship lead.
Elsewhere several drivers endured scrappy races, including Team BMR Subaru team-mates Josh Price and James Cole, who collided, ending their races.
BTCC Croft - round 14
The so-called ‘King of Croft’ reclaimed his crown in race two, with Turkington launching off the line from second on the grid and holding onto the lead thereon to take his 12th BTCC win at the track.
Race one winner Sutton - now carrying maximum success ballast - kept Turkington on his toes throughout, although he never got closer than an opening-lap move through the chicane. The attempt ended with him slipping onto the run-off area and losing ground.
Third place was taken by Collard, who had looked to challenge Sutton for much of the race until an error with two laps to go dropped him back. Shedden had a lonely run to fourth from fifth on the grid - enough for him to retain his championship lead.
Andrew Jordan (WSR BMW 125i M Sport) and Jason Plato (Team BMR Subaru Levorg) fought a mighty duel over fifth place, with Jordan just able to maintain the advantage to the flag.
BTCC Croft - round 15
From third on the randomly selected grid Jackson claimed a popular first victory of the season, just managing to fend off Sutton at the chequered flag.
Early on Jackson had to trail the pole-sitting AmD Tuning Audi S3 of Ollie Jackson, but on lap three he tagged the back of his rival, slipping by and opening out an advantage over the now chasing Rob Austin (Handy Motorsport Toyota Avensis).
While Jackson edged away, Sutton was on a charge, slipping by Subaru team-mate Plato at mid-distance and then closing down and passing Austin. Despite a four-second gap to the leader Sutton didn’t give up, starting the final lap line astern with Jackson and crossing the line side-by-side with him, only just missing out on the win.
Austin was further demoted by Plato, who claimed the final podium position.
Shedden took the final point-paying position in tenth, which was enough for him to end the weekend with an 11-point championship lead over Collard, 12-point lead over Turkington and 20-point lead over the in-form Sutton.