Saints sign Ackermann

Ackermann played in this year's Tri-Nations

South Africa lock Johan Ackermann will join Northampton Saints in January after signing with the Premiership club on Monday.

Director of Northampton rugby John Steele said: "Johan has had a distinguished career in South Africa and has played for the Springboks.

"He is a no-frills, hard lock who we believe will improve the performance of our front five even further."

The 31-year-old served a two-year ban between 1997 and 1999 after testing positive for the banned steroid nandrolone.