Reigning World Cup holders South Africa survived a huge scare in their defence opener as Wales ran them close in Wellington.
Warren Gatland's side took a 16-10 lead after 54 minutes through their only try, by Toby Faletau.
But Francois Hougaard's try and Morne Steyn's conversion killed Welsh hopes.
Hougaard's was one of two Springbok tries, Frans Steyn going over early on while Morne Steyn and James Hook kicked the rest of their side's points.
The pre-match hype belonged to a Welsh team never shy of expressing confidence that they could compete on equal terms with the Springboks in the wake of recent history.
But the opening minutes belonged to Peter de Villiers' side as they launched an efficient, try-building attack that belied South Africa's reputation as masters of kick-and-chase.
Instead from Priestland's kick-off, the ball moved through numerous hands and after a brief break for a scrum, the assault continued until Frans Steyn fended off Shane Williams and Hook to score at the corner.
The move featured a rare, but crucial missed tackle on Jacque Fourie by Wales captain Sam Warburton.
Morne Steyn added the conversion from the touchline to underline his side's confident start.
Much of the rest of the 2007 champions' opening period tactics reverted to the type that Gatland predicted.
But if the Boks' approach was familiar, so was Wales' as they attempted to keep ball in hand to move South Africa's forwards around the field as much as possible.
Morne Steyn kicked a penalty in the 19th minute after Danny Lydiate went offside at a ruck.
Wales' reward for their efforts, however, was not the try they hoped for, but two Hook penalties, the second after JP Pietersen's high tackle on Mike Phillips.
Hook also had a penalty overruled in the opening period, referee Wayne Barnes adjudging it had gone wide although TV replays suggested it may have drifted in.
At the back Hook and George North suffered occasional wobbles under South Africa's aerial barrage while up front both sides won scrum penalties and the line-out contest was also fairly even.
However, Wales were on top at the breakdown for large periods while the Boks could boast a capable defence as they went into the break 10-6 ahead.
John Smit's side began the second half with the same attacking intent as the first, but on this occasion Warburton was equal to the challenge, stripping the Boks' captain of the ball and forcing a penalty.
At the other end Shane Williams' dash down the left set up a superb attacking platform five metres from the line.
But a poor Phillips pass and Faletau's snatched attempt at taking it killed the opportunity.
Having lost centre Jean de Villiers, replaced by Butch James, to injury in the opening period, veteran lock Victor Matfield departed after Wales' early attack came to nothing.
If that was a boost, what followed lifted Welsh hopes to pre-match levels.
Jamie Roberts' charge into the heart of the defence set up a ruck from which Phillips sent Tongan-born number eight Faletau over for try confirmed by the video referee.
As befitted the reigning champions, they took the game back to Wales, drawing another penalty from Lydiate.
But the Boks spurned the penalty shot at goal, instead launching an attack from a line-out that took them back into the lead only 11 minutes after Faletau's score.
Hougaard, on as a replacement for Bryan Habana, finished off the gamble with an unopposed burst through what remained of the Welsh defence and Morne Steyn added the conversion to put them a point ahead.
Wales' response was equally impressive in its construction, but ended with Priestland hooking his drop-goal attempt from in front of the posts.
Moments later Hougaard conceded a penalty for holding on after the Boks tried to counter-attack from Priestland's superb touch-finder.
But from a wide angle, Hook could not hit the mark and when Lydiate was caught on the margins of offside from a scrum, the Boks opted for the line-out and ground out the final minutes to secure victory.
South Africa: F Steyn; Pietersen, Fourie, de Villiers, Habana; M Steyn, du Preez; Mtawarira, Smit, J du Plessis, Rossouw, Matfield, Brussow, Burger, Spies.
Replacements: James for de Villiers (24), Hougaard for Habana (61), Steenkamp for Mtawarira (55), B du Plessis for Smit (57), Muller for Matfield (44), Alberts for Spies (57).
Not Used: van der Linde.
Wales: Hook; North, J Davies, Roberts, Shane Williams; Priestland, Phillips; James, Bennett, Adam Jones, Charteris, Alun Wyn Jones, Lydiate, Warburton, Faletau.
Replacements: B Davies for Alun Wyn Jones (66).
Not Used: Burns, Bevington, Powell, Knoyle, Scott Williams, Halfpenny.
Ref: Wayne Barnes (RFU).
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