on 20 july 2009, he joined boca juniors on an initial loan for us$300,000 with the option to buy for $2.5 million, with damián díaz being sent in the opposite direction. medel said of the move "this is a dream come true. it is a very important club, and one which has players which i admire a lot, juan román riquelme, martín palermo and sebastián battaglia. he is my idol and has me very happy to play by his side". medel scored both goals in a 2–0 win in the superclásico against river plate on 25 march 2010.