Warren Gatland admitted his Wales side had simply been dominated by South Africa as they suffered a heavy 38-16 first-Test defeat at Kings Park.
Welsh hopes of a first win over the Springboks on South African soil were all but over by the time the third South African try arrived in the 21st minute, the hosts' second while Jamie Roberts was in the sin-bin for taking out Willie le Roux in the air.
It left the score at 21-6 and the tourists with no way back.
South Africa wing Bryan Habana helped himself to a brace of tries, taking his tally to 55, with Duane Vermeulen, Le Roux and debutant Cornal Hendricks also getting over. Morne Steyn added 13 points with the boot.
Dan Biggar kicked two drop-goals and a penalty for Wales, with Alex Cuthbert's late solo try, converted by James Hook, proving scant consolation.
Gatland said: "All credit to South Africa. I thought they physically dominated us in the first half and won the collisions. We just struggled a little with the pace and intensity.
"It probably didn't help having Jamie Roberts in the bin - we conceded 14 points while he was off - but I think the game had gone away from us at half-time.
"We said at the break that we needed to be much more aggressive off the line defensively and I think it was a much better performance in the second half. Hopefully it will be good for us for next week."
But Gatland did rue his side's failure to score a try with less than a minute on the clock.
Wales had cut South Africa apart, but Liam Williams' final pass to Cuthbert was behind the Cardiff Blues winger and the chance was gone.
"We started really well and had a couple of good opportunities, so to miss that chance was very disappointing. But that's rugby.
"South Africa scrambled well and they had big runners off their scrum-half and they dominated the collisions and made it tough for us to get on the front foot. It is something we need to work really hard on this week."
Gatland was full of praise for Le Roux who deservedly earned the man-of-the-match award for a wonderful display.
The Cheetahs' full-back was involved in four of South Africa's tries, and his elusiveness with ball in hand, allied to a clever mix of tactical kicking proved too much for Wales to handle.
"I thought we were very poor defending on the short side, Le Roux was an absolute pest in that respect," said Gatland.
"He was outstanding and caused us a lot of trouble with chips over the top we did not handle. On that performance you would have to say he is one of the best full-backs in the world. He was absolutely superb."
Unsurprisingly, South Africa coach Heyneke Meyer was delighted with his side's performance.
He said: "Wales are a quality side, to produce a performance like that was superb. To score five tries to one with a group of guys who have played together was very good. I thought we were awesome in the first half and I am proud to be coach of this team."