When 23-year-old tennis player, Jiri Vesely, won the Czech Open last month, he celebrated in a way most friends of National Purebred Dog Day would approve: He brought his Pomeranian, “Leo,” onto the clay court where together they did “high fives” and other tricks.

Vesely proudly announced on his Instagram page in November, 2016, that “Leo” had became a member of his family.

At the Czech Open, by the way, second-seeded Vesely outlasted Argentina’s Federico Delbonis 5-7, 6-1, 7-5. The win made Vesely the second player in history to win the tournament on three separate occasions. The first was Radek Stepanek in 2003, 2004 and 2013.