UPDATE 1-Rugby-World champions South Africa beat Wales 20-15

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By Matt Lloyd

CARDIFF, Nov 8 (Reuters) - World Cup holders South Africa opened their November international season with a 20-15 victory over European champions Wales at the Millennium stadium on Saturday.

Centres Adrian Jacobs and Jean de Villiers scored tries either side of halftime and Ruan Pienaar, starting at flyhalf for the first time in a test, kicked 10 points.

Wales missed their chance to claim only their second victory against South Africa after trailing 20-3 early in the second half.

Replacement flyhalf James Hook converted four penalties to bring Wales back into contention in front of British and Irish Lions coach Ian McGeechan, who was in the Cardiff crowd, only for the Springboks to prove their qualities in defence.

Wales's preparations were hampered by the late withdrawal of centre Gavin Henson, who failed to shake off a persistent Achilles problem that now threatens his role in the remainder of the autumn series.

Then, just five minutes after the kickoff, South Africa found a way through for the game's opening try.

JP Pietersen outjumped Shane Williams for Pienaar's high kick, quick ball offered Schalk Burger space in midfield, Conrad Jantjes and John Smit edged the Springboks closer before centre Jacobs crashed over for his sixth international try.