A luckless Wales under-21 side toiled in the sunshine but was unable to stem an irrepressible Springbok unit, losing 50-21 at Newbury.

They were dealt a blow when Argentina, who Wales beat on Tueday, took their place in the semi-finals by virtue of a bonus point, leaving Wales with a play-off showdown against England at Henley on Wednesday.

Chris Davey's side failed to benefit from a healthy share of possession, and South Africa piled on the pain. Wales played well, notably Newport prop Rhys Thomas, but they suffered in comparison with Springboks' handling and pace.

Both teams played well with 14 men, with the Springboks losing three players to the sin bin and Wales number eight James Malpas receiving a red card.

Stand-off Nicky Robinson got Wales off to a promising start, with two penalties. But South Africa replied as Bennie Adams took the restart and combined with Fourie Du Preez to send the scrum-half over under the posts.

Wing Alshuan Bock chipped Wales' Matthew Nuttall. The bounce evaded both but fell into the arms of Braden Ferreira, who put through lock Gordon Gilffian to leave Wales 14-6. Wales contained much of the Springbok charge, and created a chance for Jonathan Vaughton, but struggled against the pace.

Some slick handling made the most of an overlap for blindside Schalk Burger to touch down. Derick Hougaard added a conversion and a penalty to leave the scores 24-6 at half-time.

Hougaard added another penalty, but Wales perked up when lock Luke Charteris and flanker Mark Lewis combined to put Rhys Thomas in at the corner.

Robinson missed his conversion, Hougaard dropped a goal, and South Africa ruled out a comeback, when Ferreira touched down. Wales crossed the Springbok line, but the score was overruled after the touch judge spotted a punch by Malpas, for which he was red-carded.

Robinson chipped and gathered to score under the posts and convert. But Hougaard kicked again, and then in the last play of the game, wing Tonderai Chavanga scoreda cruel try.

Wales: 15-Gareth Swales; 14-Jonathan Vaughton, 13-David Bishop, 12-Scott Williams (Nathan Brew-52), 11-Matthew Nuttall; 10-Nicky Robinson, 9-Ricky Richards (Alyn Lake-61); 8-James Malpas, 7-Robin Sowden-Taylor, 6-Mark Lewis, 5-Luke Charteris, 4-Bryn Griffiths; 3-Rhys Thomas, 2-Rhys-Thomas Thomas (Kieran Crawford-57), 1-Paul James.

Scores: Try - Thomas, Robinson; Conversions - Robinson (1); Penalties (3) Sent off: Malpas (65mins)

South Africa: 15-Braden Ferreira (MJ Mentz-68); 14-Alshaun Bock, 13-Lafras Uys, 12-Swys Swart (Dewey Swartbooi-65), 11-Tonderai Chavanga; 10-Derrick Hougaard, 9-Fourie du Preez (Ricky Januarie-73); 8-Hannru Haupt (Jacques Cronje-51), 7-Bennie Adams, 6-Schalk Burger (capt), 5-Andries Bekker (Tim Wimble-51), 4-Gordon Gilfillan; 3-Neil Fullard (Kenny McKenzie-62), 2-David Britz (Ebrahim Moerat-80), 1-Jannie du Plessis.

Scores: Try - Du Preez, Gilfillan, Burger, Ferreira, Chavanga; Conversions - Hougaard (5); Penalties - Hougaard (4); Drop-goal - Hougaard (1)