"All you want as a player is a coach that shows such belief in you and that gives me huge confidence," said Henson, who knows that Saturday's fixture is the perfect opportunity to press his early claims to join his national coach on the 2009 Lions tour.
"I haven't had the game-time I would have liked but the coaches have had great belief in picking me and I've taken a lot from that.
"My match-fitness is not there yet but I'm in good condition and when you're playing in the Millennium Stadium, the crowd and the adrenalin gets you through."
Wales face Canada, New Zealand and Australia on the three weekends following tomorrow's match with South Africa, with Henson set to form a new midfield partnership with Cardiff Blues utility back Jamie Roberts, something the 26-year-old is really looking forward to.
"Jamie's the in-form centre in Wales and I've been impressed since his move from full-back.
"He's a huge man and makes me feel a bit short! It's nice to have some size because we've got small wingers.
"Ideally, we'd like to win all four matches. We normally get stronger as a series progresses so if we can get a victory over South Africa, it will spark some momentum."