Goikoetxea is primed to make a move this week in order to strengthen his options ahead of the new Liga campaign.
"He is a player we are following and he does indeed appeal a lot to us," the Rayo boss confirmed.
"But he has the handicap of being a non-EU player and therefore taking up one of these places in the squad.
"But, also, he has sufficient experience in order to bring a lot of quality to the club."
Meanwhile, midfielder Michel has complained about Rayo trying to sell him.
Director Feliz Uceda is believed to have travelled to London to negotiate a transfer, and Michel is angry with the Madrid-based outfit.
"Since I was 12, I have given everything to Rayo Vallecano," he stressed. "The only thing I ask is to be respected and examined on the field.
"The logical thing would be that Rayo want to retain me and say that, if a team came in, they would not sell me.
"That's the best way to rate me as a footballer.
"But if they are selling me from one place to another, we will not achieve anything."
Some clubs are keen but he only wants to play in La Liga, with Celta Vigo, Deportivo La Coruna, Valencia and Atletico Madrid all enquiring about his services.
