The 25-year-old midfielder was released from Racing at the end of last season after six years and nearly 150 appearances for the Spanish side.
The addition of Yacob could plug the hole left by the departed Paul Scharner, who was released in June, as new boss Steve Clarke looks for new arrivals to bolster his squad.
"This will give Claudio the chance to take a closer look at us, and us at him," sporting and technical director Dan Ashworth told the club’s official website.
Yacob could become the club's third signing of the summer following the loan capture of Yassine El Ghanassy, and goalkeeper Ben Foster on a permanent deal following a successful loan spell.
Jerome Thomas and George Thorne have joined the Argentine in linking up with the squad in Malmo after recovering from injury, but winger Chris Brunt has flown home for treatment on a calf problem.