South Africa and Cheetahs flanker Juan Smith has been forced to retire following the results of an MRI scan.
Smith has been sidelined since suffering an Achilles injury back in February 2011, but recently made a comeback appearance against the Stormers in pre-season.
However an MRI scan on Monday was negative, after Smith re-injured the Achilles.
An official announcement is expected to be made on Tuesday.
"It was the fans that lifted me after every disappointment of an operation and helped me scrape together hope to try and return to the field. I appreciate the support that I received through the years from my family, and that I received from Springbok and especially Free State supporters," Smith told Die Volksblad.
"There are possibilities but I haven't taken any decisions. I need to assess the physical and mental impact of my injury over the past few years. I'm first going to go for a week's vacation."
Smith played in 69 Tests for the Springboks. He was part of the Rugby World Cup-winning squad in 2007, won the Tri-Nations (2009) and was a member of the Bok squad that overcame the British & Irish Lions in 2009. In 2002, Smith was one of the stars of the South African U21 team that won the IRB U21 World Cup on home soil.
Smith also enjoyed success at provincial level with the Free State Cheetahs when they won the Currie Cup in 2005.
"This is a disappointing day for rugby as we see one of the greats of modern Springbok rugby go into retirement," said Oregan Hoskins, SARU President.
"Juan was a vital cog for every team in which he played and he will be sorely missed, not only by the Springboks, but also by the Cheetahs.
"As one of the hard men of South African rugby, Juan distinguished himself as someone that always put the team first. He wasn't someone who looked for glory, but knew what was needed to get the job done. He never gave less than his very best.
"We wish Juan all the best for his future and hope to still see him involved in rugby in some way. Thank you for your great service to rugby in South Africa in the past 10 years."
Apart from his 69 Tests and two non-Tests for South Africa, currently the 11th most by any Springbok, Smith also played in 41 matches for the Free State Cheetahs, 32 Super 12 matches for the Cats and 47 Super Rugby matches for the Cheetahs. He played a total of 198 First Class matches throughout his career, which spanned 10 seasons.
Smith made his Test debut on 7 June 2003 against Scotland in Durban and played his last Test on 27 November 2010 against England at Twickenham, where he was named man of the match.
He played in two Rugby World Cup tournaments (2003 and 2007) and was also nominated as the SA Rugby Player of the Year in those seasons.