The West London club are yet to comment on claims that a deal has been agreed with Betis, who are reported to be paying £750,000 to take the Costa Rican on loan.
The player's agent Rene Vijt has said: "At this moment, there is no agreement but that could change in a matter of seconds."
Now Betis appear to be closing on a move and their assistant coach Sergio Fernandez says he cannot wait to work with uiz.
"Bryan Ruiz is a fantastic player, links up well with team-mates, has a good shot and brings lots of creativity," Fernandez told Diario de Sevilla.
"We are confident that his game and his qualities are perfect for our team and that he can put Betis on the right place in the ranking. I think he can settle in quickly."
Ruiz is understood to be keen on regular first-team football ahead of the World Cup finals, and his national coach Jorge Luis Pinto admits he thinks a move to Betis could be the right thing for him.
"The important thing for Bryan is that he plays. If he has to go to Betis to play, it would be a good thing overall," he told Diario Al Dia de Costa Rica
"I believe that the English and the Spanish leagues are the two best. There are times when you have to put yourself first. This is the right time for him to act and if it's to go to Betis, fine.
"We are watching what is going on and that he is not losing motivation."