Oliver Gavin and Olivier Beretta have maintained the lead in the GT1 class of the American Le Mans Series after claiming a second place finish in the Grand Prix of Mosport.

Sharp pit strategy and hard driving from both drivers allowed them to bring the #4 Corvette home behind the class winning Aston Martin DBR9, although team-mates Ron Fellows and Johnny O'Connell were only able to finish fourth after an early stop-go penalty.

"Corvette Racing's primary objective is to win the manufacturers championship, and Oliver and Olivier did a great job today to protect the lead we have," Corvette Racing program manager Doug Fehan said. "But we found out today just how far great pit strategy and flawless execution will take you - and that's to second place.

"I'm proud of what we accomplished today running at such a large competitive disadvantage [with the Corvettes forced to run with an reduced air intake and at a heavier weight that the Aston Martins]. We challenged ourselves to do the best we could with what we had to work with, and I'm pleased with what we achieved. The engineers worked very hard on the strategic side of racing, the drivers worked hard in the cars, and the crew worked hard on the cars. But at the end of the day, the deficit was impossible to overcome."

The team seized the opportunity to run an out-of-sequence pit strategy by bringing in the #4 Corvette for fuel and tyres during the first full-course caution period with just 15 minutes of the two-hour, 45-minute race run.

It put Beretta just seconds behind the leading Aston Martin when racing resumed and he took the lead one hour later when both Aston Martins pitted before surrendering the place during the Corvette's second stop shortly before the hour and an half mark.

With Gavin now at the wheel, the Corvette regained the lead with just over half an hour left to run when the '009 Aston Martin pitted, but twelve minutes later the green machine passed Gavin on the Andretti Straight.

The Briton made a final pit stop for a splash of fuel with nine minutes remaining and then maintained second place to the finish.

"I think it was inevitable that the Aston was going to get in front of us," Gavin said afterwards. "They were too fast for us today. The performance adjustments have gone backward and forward all season, and it seems they've tipped too far in their direction. We were running flat out, as hard as we could.