Force India F1 boss hails team's courage in the Singapore GP

Perez looked unlikely to score any points in Sunday's F1 race, after qualifying 15th and then breaking his front wing after a mid-race brush with Adrian Sutil's Sauber.

But Force India gambled on making a fourth pitstop with 16 laps to run, and Perez utilised his fresh tyres to come through to seventh as rivals attempting to finish the race on fewer stops struggled to keep their tyres alive.

Fernley praised his team for taking a "gamble" with Perez.

"The safety car brought it all back again, and credit to the engineering team, they took a courageous decision to bring him in," Fernley told AUTOSPORT.

"At the time it looked quite outrageous, but it obviously paid off. It was a gamble and it could have gone the other way."

Perez's Force India team-mate Nico Hulkenberg utilised a three-stop strategy to beat McLaren's Kevin Magnussen to ninth place, while Jenson Button's late retirement from seventh spot meant Force India re-passed McLaren for fifth in the constructors' championship in Singapore.

"We shot ourselves in the foot in qualifying - we didn't do the best job we could have done, and it was a difficult race to see," Fernley added.

"Nico did a fabulous job, because ideally we wanted to bring Nico in and do what we did with Checo.

"However, we had to have a banker out there and Nico was obviously the banker.

"We'd already got Nico in a position where he was clearly behind Jenson and we were minimising any damage.

"What helped us actually was the fact Jenson couldn't get past Bottas.

"Had he been able to do that and that train had unlocked, Checo wouldn't have got through and Nico would have got that banker.

"Our heart was to bring him in as well, but we just couldn't afford to take that chance."