When asked about playing with European basketball legend Arvydas Sabonis, in his rookie season, Jankūnas responded: "No doubt it was the most remarkable season. It was fantastic to play with Arvydas Sabonis. I was very young, and it was very exciting. In the beginning, I was a little bit afraid and uncomfortable, but later things got easy, and I learned a lot from him. When I was a kid, I used to watch him playing on TV, and never dared to dream that I would be playing with Arvydas Sabonis. One day I woke up, and Sabonis was my teammate. It was great. He had huge experience, and gave a lot of advice to me. It was a big honor to play with him, and I hope I learned something from Sabonis."
Jankūnas played two seasons with the LKKA-Žalgiris, leading the team to a LKAL (Lithuanian League 2nd Division) title in 2003. He was named the Lithuanian 2nd Division MVP after averaging 20.0 points, 12.3 rebounds and 1.5 blocks per game.
He competed at the Reebok Eurocamp in Treviso in 2003.[3]
Jankūnas averaged 13.8 points and 8.0 rebounds per game in the 2008–09 EuroLeague season and scored a season-high 23 points in a win against the Polish League club Asseco Prokom Sopot on 18 December 2008.[4] However, Žalgiris Kaunas finished the season with a 2–8 record and did not qualify to the competition's Top 16 stage.[5] Jankūnas was named the 2008–09 season's Baltic League MVP after averaging 15.4 points and 7.7 rebounds per game.[6]
On 12 August 2021, Jankūnas re-signed with the team.[10] He played his last EuroLeague game on 3 April 2022, scoring 13 points in an overtime home victory over Crvena Zvezda.[11] On 3 June 2022, Jankūnas officially retired from professional basketball.[12]
He also helped Lithuania win the gold medal at the 2005 FIBA Under-21 World Cup.[13] He averaged 12.8 points and 8.6 rebounds per game during the tournament.
Lithuanian senior national team
Jankūnas was a member of the senior Lithuanian national team, for the first time at a major FIBA tournament, at the 2005 EuroBasket, where Lithuania finished in fifth place. During that tournament, he averaged 8.2 points and 4.0 rebounds per game. He also helped the Lithuanians win a bronze medal at the 2007 EuroBasket and another bronze medal at the 2010 FIBA World Championship. He won a silver medal with Lithuania at the 2015 EuroBasket.
A well built 2.05 m (6 ft. 8 3⁄4 in.) tall power forward, Jankūnas was a very good rebounder and scorer. He preferred to score on the inside and often drew fouls from opposing players. He could also play as a stretch four due to his consistent mid-range and three-point shot.
