Fila is renewing its relationship with the Borg family by signing Bjorn's son Leo. (FILA Tennis)

Father knows best, certainly in this case.

More than 40 years after its sponsorship of Bjorn Borg began in 1975, FILA has added the Swede's 15-year-old son, Leo, to its stable of star endorsers. His likeness will begin appearing in FILA campaigns next year.

Leo famously portrayed his father in the 2018 film Borg vs. McEnroe, conveying a young tempestuousness perhaps not so well known about Borg Sr. It's a trait sort of similar to Roger Federer's earlier, rowdier years. It turns out that Leo didn't inherit his father's sense of calm on court.  

"It’s an honor to represent FILA, a brand that has played such an important role for my father," Leo Borg said in a press release. "I am grateful for this opportunity at such an early stage in my career."

Speaking of career, Leo's is rather serious to date. He has been ranked No. 1 in Sweden in under-14 competition and won a Swedish Masters title in the same age group last year. He also garnered a quarterfinal showing at the prestigious Junior Orange Bowl in the under-14 division. Well ahead of his 16th birthday, Leo was the Salk Open's under-16 champion. 

FILA's relationship with tennis began in 1973, soon following with a winning Borg partnership. The brand dates back to 1911 in France, and now more than a century later, is again returning to its roots in a way—the roots of a grass-court giant's family tree.

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