Father, Pentti; mother, Marja; sister, Sanna; younger brother, Micke, played pro tennis until 2015.
Speaks Finnish, Swedish and English.
Favourite surface is grass and shot is serve.
If he wasn't a tennis player, he would do something with music.
Favourite sports team is HIFK, an ice hockey team in Helsinki. Also follows NHL closely.
Has trained in Uppsala, Sweden; Prague, Czech Republic and Bradenton, FL, USA.
(UPDATED 6 JULY 2021)
Became 50th World No. 1 doubles player overall and 1st from Finland on 3 April 2017.
Captured back-to-back Nitto ATP Finals titles w/Peers in 2016 and 2017, becoming 1st repeat champions at event since Bryan/Bryan in 2003-04.
Owns 24-6record in doubles finals, including 10 straight title wins w/Peers from 2016-18 and ATP Masters 1000 championships at 2016 Paris, 2017 Shanghai and 2018 Toronto.
Captured 2017 Australian Open men's doubles title w/Peers and 2016 Wimbledon mixed doubles title w/Watson to become 1st Finnish Grand Slam champion in each event.
Peaked at No. 4 in junior rankings in 2008, winning Roland Garros boys’ doubles title w/Rungkat and finishing as runner-up in Wimbledon boys’ singles and US Open boys’ doubles w/Rungkat.