Marsh replaces retired Rudolph
Veteran Australia batsman Shaun Marsh has signed a two-year contract to become Glamorgan's overseas player.
Left-hander Marsh, currently preparing for the first Ashes Test against England, returns to Cardiff following a Twenty20 spell in 2012 and will be available across all three formats of the game in 2018 and 2019.
However, the 34-year-old will arrive late next summer if he is taken in the Indian Premier League draft. He has previously proved a stand-out player for Kings XI Punjab.
"I'm extremely excited to join Glamorgan for the 2018 season," said Marsh, who replaces the recently-retired Jacques Rudolph as the Welsh county's primary import.
"I have some great memories of the club when I played in Cardiff in 2012 and I'm glad to be back.
"Securing my county future for the long term has always appealed to me, so I jumped at the opportunity when it came.
"There is a lot of exciting young talent at the club and hopefully I can put in some good performances so we can bring some silverware to Wales."
Glamorgan Director of Cricket Hugh Morris added: "We wanted to bring in someone who is experienced at international level, can bat at the top of the order and can play in all three formats of the game - Shaun ticks all of those boxes for us.
"He is a world-class performer who has played in competitions across the world and that experience will be invaluable to our young players."
View all Cricket betting