Like most squad-number incidents, it was the fault of Álvaro Arbeloa.
As we mentioned in the piece explaining how Josep Guardiola wore 9 for Spain at the 1992 Olympics and 1994 World Cup, they tend to distribute numbers for major finals based on seniority.
So it was that Arbeloa, new to the squad for Euro 2008, took number 18, which had been vacated by Cesc Fábregas, who moved to 10.
Two years later though, the full-back – who moved from 2 to 17 at Liverpool in 2006 and again at Real Madrid in 2009 – had a chance to take his favourite digits for the World Cup in South Africa, as Dani Güiza, wearer of 17 at Euro 2008, wasn’t in the squad.
That allowed Raúl Albiol – number 2 at the Euros – to switch to 18, which he was wearing at Real at the time (he had worn, in order, 27, 33, 16, 20 and 4 at Valencia, as well as 15 during a loan spell at Getafe).
In turn, Albiol’s move meant that the new players appearing in the first major finals, attacker Pedro Rodríguez and midfielder Javi Martínez, had numbers 2 (first-choice right-back Sergio Ramos wore 15) and 20 – worn by Juanito at the 2006 World Cup and Euro 2008 – available to them.
At the time, Martínez was Athletic Bilbao’s number 24, which he had had for the entirety of his career up to then, with Pedro wearing 17 for Barcelona, having had 33 and 27 before that.
The pair drew lots to decide who would wear 20, with Martinez triumphing, leaving Pedro with 2. He wasn’t over the moon but he was willing to get over it.
The truth is that neither of us were particularly excited about wearing the number 2.
So we drew lots and I got it, It doesn’t matter and it won’t be a problem.
In the end I have got that number and have to wear it.
However, a quick solution was found, with Albiol persuaded to continue in the number 2, allowing Pedro to wear 18. The attacker started the 1-0 final win over the Netherlands, who lined out 1-11, the first country to do so in a final since squad numbers were introduced in the World Cup in 1954.
With David Villa not in the squad for Euro 2012, Pedro was able to wear 7 as Spain won a third successive title and, when Villa left Barcelona at the start of 2013-14, Pedro switched to 7 there too.
However, Villa was back for the ill-fated 2014 World Cup campaign and Pedro wore 11, which he also wore at Euro 2016. It’s the number he also wears for Chelsea, having had 17 when he joined in 2015-16, switching after Pato’s departure [thanks to Nik Yeomans in the comments below for reminding us of this]. The number 7 was available in the summer of 2016 too with Ramires having left, but that went to French midfielder Ngolo Kanté.
Raúl Albiol joined Napoli in 2013 and took the number 33, which he continues to wear.