The South Africa-born right-hand batsman and right-hand seamer previously played for Northants between 2004 and 2007
Northamptonshire have re-signed Hampshire allrounder Gareth Berg on loan for the remainder of the campaign before he begins a two-year contract with the club in October.
The South Africa-born right-hand batsman and right-hand seamer, previously played for Northants between 2004 and 2007 before leaving for Middlesex.
Berg, 38, then left London in 2015 for five seasons with Hampshire, with whom he won the One-Day Cup last year and also helped the side reach this year's final in the 50-over domestic competition.
"The past five years have been some of my most enjoyable in professional cricket, winning a trophy and playing in two Lord's finals," Berg said.
"As much as I would have liked to have seen out my final years with Hampshire, I now have the great opportunity to play for Northants who gave me my first taste of county cricket."
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Hampshire's director of cricket Giles White added: "Gareth has been an outstanding player and excellent club man.
"This year, first-team appearances have been limited and this move represents a great opportunity at this point in his career.
"On behalf of everyone at Hampshire, I'd like to thank Gareth for his great contribution to the club and wish him and his family well for the future."
"It's great to have Gareth join us," said Northants' red-ball captain Adam Rossington.
"He's a very good cricketer with bat and ball and it's not very often an allrounder of Gareth's quality becomes available, so it was a no brainer to bring him in."
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