Argentine trialists Fernando Screpis and Damian Gimenez

Spaniard Palazuelos, 24, is a free agent after leaving Aris, while Screpis, 28, is no longer wanted by Defensores de Belgrano.

Fellow Argentine Giminez, 25, has been made available by Neuva Chicago after they fell out his country's top flight.

The players are with Hearts at their pre-season training base in Austria.

The Edinburgh club are expected to make a decision on their futures next week.

Assistant coach Stevie Frail said of the Argentines: "They are both left-footed and look good, but we will need to see them in games.

Panathinaikos want Ruben, but he would prefer to go to Hearts Agent Paulo Barbosa

"But, given we're already at this stage, you can assume they are good players."

Palazeulos' agent, Paulo Barbosa, told the Edinburgh Evening News: "We are talking about a contract agreement with Hearts right now, perhaps for four or five years.

"Ruben wants to sign. Panathinaikos want him, but he would prefer to go to Hearts. Scotland is better football for him.

"Ruben is a good player. He was one of the best players at Aris.

"He plays defensive midfield and is left footed but can also use his right foot very well.

"He is a very tough kind of player who was raised in the footballing schools of Santander."

Hearts agreed a fee of �50,000 with Leicester City on Thursday for the services of former Rangers midfielder Stephen Hughes, who is now discussing personal terms.

The Tynecastle club have already added midfielders Michael Stewart, previously of Hibernian, and Laryea Kingston, purchased from Terek Grozny.