Bojan had been keen on a return to Spain as he sought more game time than he might be guaranteed under Mark Hughes.
“I had the option to go to Girona but finally the negotiations broke down," the 27-year-old forward told RAC1.
Bojan was also wanted in France and Germany while Malaga were among the clubs keen in La LIga.
He added: “I was very clear that I wanted to go back to Spain. Whoever I most value is who really loves me, and in this sense, Alavés are the ones who have shown the most interest in having me."