Isco is out of contract next summer and has so far refused to commit to Madrid beyond then, saying recently that a decision will be made based on his involvement between now and the end of the season.

It's fuelled speculation that the Spain international may not only leave the club, but that he could make a sensational move across the Clasico divide to Barca.

"All good players are welcome," Alba said at the opening of a football school carrying his name in his hometown of L'Hospitalet del Llobregat.

"I have an appreciation for Isco. I know him from when we were at Valencia together and I know that he has a lot of quality. Anything else, time will tell."

Only 12 players have gone on to play for Barca having previously played for Madrid, according to Mundo Deportivo.

The last was Samuel Eto'o, via a spell with Mallorca, while current Blaugrana coach Luis Enrique was the last player to make the move directly when he swapped the Bernabeu for Camp Nou in 1996.

Luis Enrique spent eight years as a Barca player and has been in charge of the first team since 2014, although he's currently under pressure following the 4-0 Champions League loss to Paris Saint-Germain.

However, while he's yet to commit to the club beyond the expiration of his contract in the summer, he has received the support of his players this week, with Alba echoing Gerard Pique's comments that the squad are all behind their manager.

"The critics go for one person one day and another the next, but I'm with the manager until the death," the left-back said in defence of his coach.

"He has helped me in many areas where I wasn't great [before]. We have had three magnificent years with him and we're all behind him. He's the best manager we can have. He knows the club and he knows us.

"We win and we lose together. We all share the blame, but don't forget that we're in the final of the cup, we still have a chance in La Liga and we will give our all in the Champions League."