The Manchester United winger took to the photo-sharing app to wish former Aston Villa midfielder Stiliyan Petrov a happy 36th birthday.
The brave Bulgarian midfielder successfully recovered from acute leukaemia before he retired from professional in football in May 2013.
Young, who played alongside Petrov for four years at Villa Park, sent a touching message to the former Celtic midfielder via his Instagram page.
Young posted the above snap and wrote: “Happy Birthday To My Mate and Inspiration, Stiliyaneeee. Happy B’day, Stan!”
Petrov, who captained the Birmingham side before illness promoted the midfielder to suspend his career, scored 12 goals in 218 appearances during a seven-year career at Villa.
The former Bulgaria international was named Villa players’ player of the year in 2009 and 2012.
Young, meanwhile, left Villa to join United in a £16m deal in 2013 and the midfielder won the Premier League title in his first season at Old Trafford.
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