Fly-half Biggar will be involved in his fourth straight Wales clash this autumn and will win his 60th cap against the giant Springboks in Cardiff.
“We will find out how decent an autumn we have had at about 4pm on Saturday,” Biggar said.
“If we get a win, backed up with the performances against Australia and New Zealand, it will be a pretty decent campaign building nicely into the Six Nations.
“It’s massively important we get a win, that’s the only thing that matters for us as a squad.
“We want to make sure we are winners on that field rather than being positive about playing well, but not quite getting over the line.”
Wales have won their last two home games against South Africa, a team who always provide a physical threat.
Biggar himself has faced the men from the rainbow nation on six separate occasions and said: “When you go into a game against Australia, you know they are going to come up with a lot of intricacies in terms of back play and have a lot of variation.
“It’s the same with the All Blacks, England and Ireland, teams like that.
“South Africa are trying to play a fair bit of rugby as well when they get good field position.
“But you know they are going to be pragmatic – the ball is going to be in the air quite a bit.
“You know you don’t want to give them too many driving line-outs because it’s a massive strength of theirs. In terms of physicality and the size of their men, they are going to be your toughest opponents.
“So it’s about us barring up on the weekend and sometimes not doing the pretty things. Sometimes you’ve got to knuckle down a little bit, get your boots dirty and really front up.
“That’s the main message and Shaun (Edwards) has been drilling that into us all week in terms of fronting up and delivering a physical performance and stopping these guys.
“If they get a roll on and you are on the back foot, it’s a tough day.”
Biggar will partner scrum-half Aled Davies in Saturday’s game in Cardiff for the first time.
After defeats to Australia and New Zealand either side of victory over Georgia, the Ospreys man knows just how important a win is this weekend.
“Our record against the Springboks in the last few years has been pretty good in terms of results. It’s about taking confidence from that,” said the fly-half.
“We are aware of the threats they pose in terms of physicality and the sheer size and strength of the side. But we tend to get better as campaigns go on, so it’s about making sure we peak on Saturday and pick up a win.
“We get another chance to sample 70,000 at Principality Stadium, playing against one of the best teams in the world.
“It’s important for us to keep pace with England, Ireland and Scotland and find some confidence and continuity for the Six Nations.”
