Billy Root has joined Glamorgan on a two-year deal after cutting his time with Nottinghamshire short.
Root, the 26-year-old younger brother of England Test captain Joe, had 12 months remaining on his contract at Trent Bridge.
However, the end-of-season signings of Joe Clarke, Ben Duckett and Ben Slater, threatened to restrict his future appearances.
"We're sad to see Billy go but understand that he wants more regular playing opportunities, something which has been hard to come by over the past year," said Nottinghamshire director of cricket Mick Newell.
"He has the ability to play in all three formats, as he has shown during his time with us and I am sure he will relish his new challenge with Glamorgan."
Glamorgan claimed the County Championship wooden spoon in 2018 and lost young talent Aneurin Donald to Hampshire to rub salt into their wounds.
"Over the course of the campaign it became apparent we needed to supplement our batting stocks and in Billy we have signed a player who is still young but has experience playing Division One cricket and is hungry to succeed," said Glamorgan director of cricket Hugh Morris.
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