Celtic and Athletic Bilbao are two clubs and sets of fans that share a great relationship. But the latest transfer news regarding the Spanish club might not be a good one when it comes to the Hoops.

It has been quite some time since a player came through the Celtic youth ranks and became a first-team starter.

The likes of Stephen Welsh, Mikey Johnston, Anthony Ralston and a few others have been involved here and there. But overall, nobody really has gone on to become a key player in a long, long time.

In fact, the last to do so was Kieran Tierney. He became a top player at Celtic, left for Arsenal in a Scottish record move, spent six years there and has returned to Glasgow since then. But not has been able to make the jump from the youth ranks to the first-team's starting XI in that period of time.

It is not like Celtic have had not talent either. But for one reason or another, it has just never worked out.

Karamoko Dembele was earning comparisons to Lionel Messi during his youth days but never made the grade at Celtic at the senior level. Ben Doak left after just two appearances to join Liverpool. He is the one who had the best chance of making it. And Rocco Vata departed after not getting enough chances, and understandably so.

Now, Celtic have another wonderkid in their youth ranks. Someone who is already drawing the interest of clubs around Europe and has been called up to the Spain U15 set up.

According to La Cantera de Lezama (via AthleticXtra), Athletic Bilbao are following Zion Pullan.

Pullan has 58 goals and 35 assists with Celtic Under-15 and U-17 teams. He was recently called up to the Spain Under-15 national team.

Pullan can play as a winger as well as a forward. And it is safe to say that he is very highly regarded.

Of course, when big clubs have come calling, most Celtic talents have decided to leave rather than wait for their chance at Parkhead.

It is understandable, too. Celtic simply have not been able to give enough opportunities to their youngsters. The pathway into the senior team simply does not exist. And that has made the decision to leave far easier for many. They have little to lose to be very honest about it.

It remains to be seen what the future holds for Pullan. But this Athletic Bilbao interest is not good news if you are a Celtic fan.

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