James Dayton's desire to play for Oldham impressed boss Lee Johnson.
Oldham beat off fierce competition to sign the midfielder, who was officially unveiled by the npower League One club on Monday.
Dayton moved to Boundary Park from Kilmarnock after rejecting the SPL side's offer of a new three-year contract.
"I know there were other clubs who would have paid more than we can which shows a desire by James to be here at Oldham," Johnson told the Latics' official website.
"James is proven. He has done very well in Scotland and Kilmarnock wanted him to stay.
"I am delighted to have signed a player of his pedigree and talent. I am sure he will do very well for us."
Dayton, 24, has signed a two-year deal with Oldham.
The Londoner was at Crystal Palace between the ages of 10 and 20 and had loan spells with Yeovil and Crawley before signing for joining Kilmarnock in August 2010.