Athletic Bilbao could be forced to pay Javi Martinez's former club Osasuna €800k following the midfielder's move to Bayern Munich.
Granada and Osasuna both made signings on Thursday ahead of the 2012-13 La Liga campaign.
Barcelona set up a blockbuster Copa del Rey quarter-final against Real Madrid without ever having to hit top gear against Osasuna.
Barcelona moved a step closer to a possible Copa del Rey quarter-final showdown with Real Madrid after winning the first leg of their last-16 tie against Osasuna 4-0 at the Nou Camp.
Villarreal have agreed a deal for Osasuna attacking midfielder Javier Camunas.
Osasuna have fired coach Jose Antonio Camacho after falling into the relegation zone this weekend.
Osasuna striker Walter Pandiani has claimed Cristiano Ronaldo "has a screw loose" in the wake of their verbal spat in Real Madrid's shock loss on Sunday.
Real Madrid coach Jose Mourinho could not fault his players for their efforts but admits Sunday night's 1-0 defeat to struggling Osasuna has left them in a "much more difficult situation'' with regards their pursuit of Primera Division leaders Barcelona.
Atletico Madrid have completed the signing of Osasuna winger Juanfran Torres. Juanfran, who will cost Atletico an initial €4.25 million, has passed his medical and penned a deal that will tie him to the capital club until June 30, 2015.
Cristiano Ronaldo has been included in Real Madrid's squad for Saturday's Primera Division match with Osasuna after making a speedy recovery from injury.