Hartley was confident before the Paul Ricard race that the team had solved the reliability issues and would be able to grab their first win. The pair qualified on the front row and Hirschi was first away when the lights went out.
After a double stint behind the wheel, the Swiss driver handed the car over to Hartley 48 seconds behind the race leader. Hartley closed the gap on the frontrunners at around four seconds a lap and was soon on to the back of the leading car, which he dispatched shortly afterwards, and was never headed.
"It was a really great way to end the year and the win had been a long time coming," said Hartley. "It's been surprising we hadn't won one before now.
"The car's been really reliable recently and we would have won the race at the Red Bull Ring if we hadn't had the problem. Finally it's all come together."
It wasn't all plain sailing for the pair in the Murphy Prototypes car, though. During Hirschi's second stint behind the wheel, the front right disc rotor parted company with the bell.
Brake problems are a worst-case scenario for drivers and teams, but the car was thoroughly checked over before Hirschi was sent back out into the fray, and although he had no front right brake, the rest of the system was deemed to be working properly.
The car was a little off the pace and when Hartley took over he needed a few laps to adapt to the unbalanced braking combination.
But he was soon back on to the pace, passing all and sundry on his way to eventually taking the win.
"The race wasn't all as it seemed. We had brake issues that meant we had nothing on the front right wheel. All the braking was on the left and the rears and towards the end of the race the left front was down to the canvas.
"It got pretty close in the last few laps and we were all a little stressed. If the race had gone on for another five or 10 minutes we wouldn't have made it across the line. Seeing the chequered flag was a relief to say the least. It was pretty nervy that's for sure.
"Everyone at Murphy Prototypes deserved the win because they've all worked so hard. I'm really proud of everyone."
The win, and his undoubted speed during the season, put Hartley in the box seat for a fulltime driving job next year, and if a report published on the Autosport website is anything to go on, the young Kiwi is being lined up for a Porsche drive.
"Former Red Bull junior driver Brendon Hartley has emerged as a firm contender for a seat with Porsche's 2014 World Endurance Championship squad," wrote Gary Watkins.
"The 23-year-old Kiwi is known to be in negotiations about driving the German manufacturer's new 2014 LMP1 hybrid. Hartley is in the running for a full-time seat with Porsche, which already has four drivers under contract for next year.
"It plans to field three drivers in each of its two entries over the full WEC, not just the Le Mans 24 Hours and the build-up races."
Hartley, who is expected to test the Porsche LMP1 in the next few weeks, was not available to comment on his possible works drive. But it has been rumoured he will be strapping into a Porsche for a test drive in the next five to six weeks.
In the meantime, the New Zealander will be resuming his simulator testing duties with the Petronas Mercedes Formula One team in England.
