Sepang is a "complete circuit" that tests the physical limits of drivers, according to former Formula One star Giancarlo Fisichella.
The Malaysia Grand Prix accounted for one of three race victories recorded by Fisichella during a 13-year F1 career, with the Italian driving his Renault to victory in 2006.
And, with the F1 season arriving in Malaysia for the second round of the 2015 season, Fisichella believes the circuit presents one of the toughest challenges on the calendar.
"The Malaysian circuit is very technical, it is a really hard test as a driver," he told Perform. "The circuit has a lot of tight turns, there are several types of curves.
"It starts with a number of hairpin corners which must be faced in first gear, and ends with large and fast corners. In this respect, we are talking about a complete circuit and it is very difficult from a physical point of view.
"It is very hot with temperatures going up to 35-40 degrees, together with a humidity which can reach 100 per cent.
"After 10 laps, drivers are already exhausted, so you can imagine how we feel after completing 60 or 70 laps during the race.
"The Malaysian Grand Prix is very tough, but you feel rewarded especially when you win, because it means that you are also fit physically."