Gillingham have signed Lee Martin on a two-year deal, while Deji Oshilaja has returned to the League One club on a season-long loan from Cardiff City.
Midfielder Martin, 29, recently left Millwall after his contract expired, having played 69 games in three years with the Lions.
Defender Oshilaja, 23, spent most of last season on loan with the Gills.
“For me, Lee’s a Championship player. I think we’ve secured a real talent,” said Gillingham boss Justin Edinburgh.
“I think we all know Deji’s qualities. He’s a fantastic centre-half and he and Max Ehmer will form a formidable partnership this season.”
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