Chasing 160, Rossouw and Sarfraz smashed rapid fifties, putting the Gladiators back in control after the team stumbled early in the match following a triple strike by Kings’ pacer Sohail Khan.
Rossouw scored a quick half-century as he hit rapid boundaries to break through the pressure, taking his side to 97-3 at the end of 12 overs.
Sohail earlier removed Ahmad Shehzad, Kevin Pietersen and Asad Shafiq in quick succession, putting the Gladiators well under pressure in their chase of 160.
Sohail removed Ahmad Shehzad, Kevin Pietersen and Asad Shafiq, as Quetta stumbled early in their innings in pursuit of 160.
Earlier, Kings set Quetta Gladiators a relatively easy target of 160, after Quetta won the toss and chose to field first.
Kumar Sangakkara men started their innings on an aggressive note, but soon lost pace with the fall of Shahzaib Hasan and Chris Gayle.
Tymal Mills got Gladiators the first breakthrough. Thisara Perera struck second, taking danger-man Chris Gayle down in the fifth over.
Babar Azam and Kumar Sangakkara steadied the ship again until the end of the 11th over, when the former Sri Lankan batsman was caught out off Perera. Sangakkara made 25 runs off 22 deliveries, the second highest score of the innings.
Shortly afterwards, Mohammad Nawaz struck to claim his first wicket of the match, dismissing Kieron Pollard for 14 runs.
Shoaib Malik and Ravi Bopara scored 15 and 16 runs respectively, while Sohail Khan chipped in with 2 runs before being run out by Gladiators skipper and wicket keeper Sarfraz Ahmed.
Azam lost his wicket in the 18th over with a 42-ball half century. Kings scored 159 runs for the loss of 9 wickets after the end of 20 overs.
The match started at 09:00 PM Pakistan time, which corresponds to 08:30 PM Indian time, 05:00 GMT and 08:00 PM according to UAE time.
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Karachi Kings & Quetta Gladiators SquadsKarachi Kings: Kumar Sangakkara (captain), Shoaib Malik, Chris Gayle, Babar Azam, Ravi Bopara, Imad Wasim, Mohammad Amir, Safiullah Bangash, Shazaib Hasan, Sohail Khan, Kieron Pollard, Ryan McLaren, Khurram Manzoor, Kashif Bhatti, Abrar Ahmed, Abdul Hameed/Hasan Mohsin, Mahela Jayawardene, Usama Mir, Rahat Ali, Amad Alam.
Quetta Gladiators: Sarfraz Ahmed (captain), Umar Gul, Asad Shafiq, Ahmed Shehzad, Mohammad Nawaz, Kevin Pietersen, Luke Wright, Rilee Rossouw, Mahmudullah Riyad, Anwar Ali, Tymal Mills, Hassan Khan, Nathan McCullum, Thisara Perera, Bismillah Khan, Mir Hamza, Zulfiqar Babar, Saad Nasim, Umar Amin, Noor Wali.