Sanchez ??? who had the word ???Abuela??? (Grandmother) stitched into his spikes ??? produced a photograph of his grandmother from his vest after crossing the line and kissed it before breaking down in tears.
The US-born hurdler later sobbed uncontrollably as he stepped up to collect his medal ??? the first time he had registered a podium finish at any major championships since 2007.
Sanchez later wept again as he recalled the dark day in Beijing four years ago when he had learned of his grandmother???s death.
???When I got the news my grandmother had died I cried all day and I wasn???t sure I would run but I did and failed to make it out of the heats,??? said Sanchez.
???I made a promise that day that I would win a medal for her ... it took me four years.
???I brought a picture of her to the Games and kept it under my bed and then brought it out for the final.
???I???ve been very emotional all week wanting to keep my promise but after 14 years at the top I had so many races under my belt since my first major championships the 1999 worlds I didn???t know whether I had it in me.
???It???s just an amazing feeling. Then when I was on the podium and it started raining it felt like my grandmother was crying tears of joy.
???The day she died in Beijing it broke my heart,??? Sanchez said. ???That???s why I ran with the picture close to my heart.???
Sanchez???s victory was as unexpected as it was dramatic.
No-one had given the veteran a chance of upsetting Javier Culson, the brilliant Puerto Rican who has been unbeaten all year.
