Former Carlisle United defender Macaulay Gillesphey has made a transfer window move to one of the Blues' League One rivals.
He has joined Charlton Athletic in a permanent deal from Championship club Plymouth Argyle.
Gillesphey, 28, has signed a two-and-a-half year deal with the option of a further year after the Addicks paid an undisclosed fee for his services.
It ends his two-and-a-half year stint at Argyle, where he made 91 appearances, a spell which included promotion from the third tier last season.
He joins a Charlton side who sit 13th in the table.
"I'm delighted to bring Macaulay in - he's a man mountain which helps and is left-sided, which gives us a little bit of balance," Charlton boss Michael Appleton told the club website.
“He's very comfortable in possession of the ball, very dominant in the air and he's someone who was part of a title-winning Plymouth squad last season.
"I'm really excited to start working with him.”
Gillesphey had three spells with Carlisle in the early stages of his professional career.
He joined on loan from Newcastle United in the 2015/16 season and made 27 appearances under Keith Curle.
Manager Curle then brought him back on loan for the full 2016/17 campaign, which saw Gillesphey tot up 36 more appearances.
A permanent move to Brunton Park then followed under John Sheridan in 2018, with Gillesphey playing 30 times that campaign under Sheridan and his successor Steven Pressley.
Two years in Australia with Brisbane Roar followed before Plymouth brought him back to England in the summer of 2021.
Among his other highlights with the Devon club was a goal against Chelsea at Stamford Bridge in the FA Cup in 2022, one of four goals he scored for Plymouth.
"I'm really happy to be here," said the defender of his move to The Valley. "It's a massive club, with huge potential, and when I found out they were interested it was a no-brainer."
Gillesphey could face his former club when Carlisle face Charlton in south London on March 9. His debut could come against Peterborough United.
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