Is Beast the new Os?
The 32-year-old, affectionately known as Beast, has put in some solid performances in the green and gold recently and Proudfoot says his experience has been invaluable to the Boks' cause this year, especially for the younger props in the team.
Proudfoot has even compared Mtawarira and his experience with that of two-time World Cup-winning prop Os du Randt.
"The guy, with 95 Test caps, brings a lot of experience," said Proudfoot.
"He is the most experienced South African prop of all time.
"I played against Os [Du Randt]. Os won two World Cups and they are similar type of players. You can't chuck that type of player away.
"When Jake [White] went and fetched him [Du Randt] out of retirement to come back and play at that World Cup in 2007, he was incredible.
"The front row is about experience, it is about learning. Every scrum presents you with a different challenge and you only pick that up by learning the trade at the coalface, so I think Beast is comfortable where he is.
"He is such an integral figure in the team. When he stands and talks, the guys listen.
"I think Beast is really focussed on what he wants to achieve and the parameters Allister [Coetzee] set down in the beginning of the year about conditioning, about work rate, he [Mtawarira] has taken it on board."
Proudfoot said Mtawarira is eager to match anything the younger players in the squad a can do.
"When a senior guy with 95 caps sets that type of environment it is very easy for the younger guys to follow.
"That's leadership. So, I'm very proud of what he has achieved, not just his scrummaging ability, but his play and his defensive play," Proudfoot added.
By Warren Fortune