DURHAM, FRIDAY – Sri Lanka gave a woeful batting performance against South Africa to undermine their chances of qualifying for a place in the World Cup semi-finals when they lost a crucial contest played at Chester-le-Street here on Friday by nine wickets.It was a must win game for the Lankans and after a good beginning when they scored 67 runs off the first ten powerplay overs, their batting simply fell away and they limped to 203 largely through poor decision-making with the bat.