Xabi broke his pinkie toe (jk, it's his fifth metatarsal bone) in training this morning. He's estimated to be out for three months, same as when Marcelo had the same injury last season.
Xabi had been operated on two months ago and had been spending his summer vacation on a personal training schedule to maintain his muscle tone. He had been expected to make his first appearance of the season at the Trofeo Santiago Bernabeu game.
(Someone get the sad Xabi gif.)
Source.