The forward is likely to leave the Swans this summer and the Spanish side are said to be keen on a deal.
The Spaniard looks set to leave the Swans this summer after failing to impress while out on loan at Napoli last season and also struggling for Garry Monk’s side the season before that.
That has led to a number of clubs being interested in the player, with Spanish sides Malaga and Deportivo both registering an interest before now - with the South Wales Evening Post reporting as much. The latest to join the chase are Rayo, with their sporting director sizing up a move for him.
However, according to Marca, there are several obstacles they would have to overcome to secure the player. The first of these would be his wages, with the La Liga outfit unable to match his relatively high salary at the Liberty Stadium, while his asking price may also be a stumbling block.
The one positive they are clinging to, though, is his desire to leave the Welsh side, with them hoping that could be used to convince the club to either part fund his wages or release him entirely, thus making a move considerably easier.
Should Swansea stick with Michu?
If Swansea are unable to sell the forward, it is possible that Garry Monk may look to try and reinvigorate his career.
While the last two seasons have been disappointing for the Spaniard, they have largely been because of his struggles with several injuries, most notably the ankle problem he struggled with during the 2013/14 season.
His first season in the Premier League showed how good he can be, and with the Swans currently only having Bafetimibi Gomis and summer signing Eder up front, Michu could prove to be a useful back up if they can keep him fit.