As the Friday rain continued over into the weekend to create conditions only marginally better than the rain that cancelled the second race of the weekend Carlos Sainz Jr. won the 40-minute British Formula Three International Series race from Spa-Francorchamps.

In the weekend's opening race Sainz had got the jump off the line against poleman Felix Serralles, but it was the Puerto Rican who won the battle to La Source to lead the opening lap with Sainz in second and Daniel Juncadella in third as the best of European racers running as Invitation Class entries.

Just as Serralles had taken the lead in Friday's race Sainz moved into the lead, driving past on the inside before Les Combes into to move back to the outside for the optimum line into the corner. From that point on Sainz was uncatchable, leading by a second after just half a lap in the lead his task was made easier when Serralles pirouetted off at Pouhon, letting Tom Blomqvist into second place (Juncadell another to trip up a Pouhon in the conditions) and Sainz Jr. into a lead of nearly six seconds.

The biggest threat to the Red Bull sponsored driver was tenth place Sven Muller. The German crashed heavily at Eau Rouge, prompting a safety car while the Prema Powerteam Dallara was cleared off the track.

The clear-up left just ten minutes remaining, but Sainz Jr. saw off any potential attack with a fine restart before he started to rebuild his lead over Blomqvist to lead by 5.604 seconds at the end of the race from Blomqvist and Serralles whose spin had only set him back third. P Juncadella's had demoted him to tenth place, but climbed back to eighth passing first Muller then Lynn shortly before the mid-race safety car interruption. Jazeman Jaafar was fourth, with Michael Lewis fifth after passing Jack Harvey in the closing laps

With Harvey finishing in sixth overall, and fourth among the British series entrants Serralles podium visit was enough to give him the lead in the championship ahead of the final stretch of races back on UK soil.

Changes in position – in some contrast to the earlier race – were few and far between, drivers seemingly more concerned with the conditions than with close battling. Even the standard move – displayed perfectly by Sainz in the move for the lead – was seldom seen.

However, after qualifying tenth and losing places in the opening lap Harry Tincknell was one of the race's men on charge. Handed a place in the top by Muller's off the Devonian passed Alex Lynn for ninth in the first lap of racing after the safety car had returned to the pits, holfing off Euro F3 driver Emil Bernstorff by just 15 hundredths at the line, as  Lynn slipped back to eleventh overall.

Adderly Fong took the win in the National Class, untroubled by his trio of class rivals as he beat both Hannes van Asseldonk and Pietro Fantin by finishing 17th overall.