Alex Cuthbert says Wales must take their chances if they are to beat South Africa in the second Test.
The winger scored a memorable second-half try before the Springboks went on to win 38-16 in last Saturday's first Test.
Wales face South Africa in Nelspruit on Saturday and Cuthbert says there is plenty to work on ahead of the game.
"It's just the fine margins and that's what international rugby is all about," said the 24-year-old.
The Cardiff Blues player added: "I think we had more line breaks than them in the first half and we didn't take any. They had half of what we had and they took every one."
Assistant coach Shaun Edwards hopes Wales can produce an improved performance on Saturday after their slow start in Durban.
Wales conceded four tries during the first half and, not for the first time, struggled in the opening game of a Test series against a southern hemisphere side.
Wales failed to produce in opening games against South Africa in 2008, New Zealand in 2010 and Australia in 2012, but were much improved come the second contests with their hosts.
"It's the same old story," Edwards said. "It happened in 2008 here and it happened in 2009 with the Lions here, too
"In the first half of the first match of a series, we have struggled to get up to pace, intensity and the speed of the game. Hopefully we can give a better account of ourselves next week.
"I thought we were definitely better in the second half. But when you lose the penalty count 13-7 and they spend seven-and-a-half minutes in your 22, you are really fighting with your backs against the wall."