SHARJAH – Rahmanullah Gurbaz hit a superb century before leg-spin magician Rashid Khan marked his 26th birthday by taking five wickets as Afghanistan thrashed South Africa by 177 runs in the second one-day international on Friday.Gurbaz hit 105 as Afghanistan made 311-4 before the Proteas lost nine wickets for 61 runs to be bowled out for just 134 in the 35th over.It was the seventh century in the 22-year-old’s Gurbaz’s ODI career and included 10 fours and three sixes. “I had a hamstring injury but I try my best to stay on the ground and do my best for the team,” said man-of-the-match…