After averaging 8.0 points and 4.6 rebounds over five Summer League games for the Utah Jazz, Motum signed a non-guaranteed contract with the franchise on 26 August 2014. He was later waived by the Jazz on 25 October 2014 after appearing in one preseason game.
On 3 November 2014, Motum signed a conditional two-year deal with the Adelaide 36ers of the National Basketball League. Backing up 7'1" Luke Schenscher at centre in his debut game on 9 November, Motum recorded 28 points and 6 rebounds in the 36ers' 100-107 loss to the Sydney Kings. While the 36ers lost their first seven games with Motum, they began a fightback effort to try and qualify for the 2014–15 NBL playoffs as they won eight out of their next 10 games. During this time with Schenscher restricted by an ankle injury, Motum moved to the starting lineup at power forward and 6'11" Daniel Johnson playing at centre, with the two forming a formidable front court combination. On 23 January 2015, he was named Player of the Week for Round 15 after recording 31 points and 13 rebounds on 16 January against Perth, and 17 points and 11 rebounds on 18 January against Wollongong. On 5 February 2015, Motum was named the Player of the Month for January after leading the 36ers to a monthly record of 5-1 while averaging 20.8 points over the six games. In 24 games for Adelaide in 2014–15, he averaged 17.5 points and 7.1 rebounds per game. In June 2015, Motum exercised the NBA and European out clause in his contract with the 36ers, parting ways with the club.
Return to Utah
In July 2015, Motum re-joined the Utah Jazz for the 2015 NBA Summer League. In eight Summer League games for the Jazz, he averaged 8.3 points and 3.9 rebounds per game.
On 4 August 2015, Motum signed a one-year deal, with the option of a second, with Žalgiris Kaunas of the Lithuanian Basketball League. On 7 August 2016, he re-signed with the team. Motum had an amazing second season, becoming one of the team leaders in the Euroleague, and in the LKL, turning the criticism of the first season to praise in the second one. During his time with Žalgiris, Motum won the LKL championships in 2016 and 2017, and the KMT Cup in 2017.
On 29 June 2017, Motum signed a one-year deal with Turkish club Anadolu Efes.
Valencia Basket
On 2 July 2019 Motum signed a two-year deal with Spanish club Valencia Basket. After averaging 5.9 points per game, he ended his contract on July 4, 2020.
Motum is the son of Greg and Leonie Motum, and has a sister, Anna. On 15 August 2017, he proposed to former Žalgiris TV presenter Martyna Marmaitė which he met while playing for Žalgiris Kaunas.
