The Colombia international spent three seasons at the Bernabeu after a big-money move from Monaco in 2014/15, but failed to live up to expectations during his stay in the Spanish capital.
Rodriguez was linked with a host of big names this summer as an exit from Madrid looked increasingly likely, with the likes of Chelsea and Manchester United mentioned as being in for him shortly before his switch to the Allianz Arena.
The 26-year-old will now be looking to bounce back in the Bundesliga, but Sanchez believes he lacked the character to try harder to win manager Zinedine Zidane around during his final season with Real.
‘The character of a player must be solidified and that is exactly what James was missing,’ Sanchez told Marca.
