NBA G League Ignite (2023–2024) On May 31, 2023, Buzelis signed with the
NBA G League Ignite. Buzelis for the first time was selected to play in the
2024 Rising Stars Challenge as a part of the Team Detlef with which he lost in the final 25–13 to the Team Jalen. During the
2023–24 NBA G League season Buzelis averaged 14.1 points, 6.6 rebounds and 1.9 assists per game.
Chicago Bulls (2024–present) 2024–2025 season Buzelis was selected with the 11th overall pick by the
Chicago Bulls during the
2024 NBA draft. Buzelis reportedly worked his way as a projected top 5 in the pre-draft process as teams were interested in his size and feel for the game putting him as a top 5 pick commonly to the
Detroit Pistons who decided to go with Ignite teammate
Ron Holland. Other teams passed on Buzelis dropping him to his hometown Bulls. He signed a rookie-scale contract with the Bulls on July 2, 2024. Buzelis made his NBA debut on October 23, 2024, in a 123–111 loss to the
New Orleans Pelicans. On January 20, 2025, he committed to the
NBA Slam Dunk Contest during the
2025 All-Star weekend, becoming the first Lithuanian player to do so. He also became the first Bulls player to participate in the contest since
Tyrus Thomas in
2007. On February 4, Buzelis scored 24 points while shooting 10-for-10 from the field in a 133–124 win over the
Miami Heat. In addition to participation in the NBA Slam Dunk Contest, Buzelis was also selected to play for
Mitch Richmond's team during the
2025 Rising Stars Challenge, where his team was eliminated in the semifinal 40–39. On March 22, he put up a career-high 31 points in a 146–115 victory over the
Los Angeles Lakers. On March 29, Buzelis scored 28 points, grabbed nine rebounds, dished out six assists against the
Dallas Mavericks and became the third Bulls rookie to achieve such game statistics, the other two being
Michael Jordan and
Charles Oakley. On April 4, Buzelis put up his first career double-double with 12 points and 12 rebounds in a 118–113 win over the
Portland Trail Blazers. When his playing time increased in the second half of his first NBA season and Buzelis started in 31 games, his averages were 13 points (47.3 percent from the field) and 4.5 rebounds per game. On May 20, 2025, Buzelis was included to the
NBA All-Rookie Second Team.
2025–2026 season Buzelis began his
second NBA season with a dominating performance of 21 points, 6 rebounds, 3 blocks and together with
Nikola Vučević (28 points) led the Bulls to a season-opening 115–111 victory versus the
Detroit Pistons. When the Bulls traded their long-term players
Nikola Vučević,
Coby White, and
Ayo Dosunmu just before the NBA trade deadline, Buzelis's role in the team further increased and he became Bulls' leading scorer. On February 13, Buzelis was selected to play for the
Vince Carter's team during the
2026 Rising Stars Challenge and his team won the tournament. On February 21, Buzelis achieved a new career-high by
blocking six shots, along with scoring 15 points, grabbing six rebounds, making two steals, and dishing out three assists, however the Bulls lost the game 126–110 to the Detroit Pistons. On February 24, Buzelis set a new career-high in scoring with 32 points against the
Charlotte Hornets, however the Bulls lost the game 131–99. On March 10, Buzelis set another career-high by scoring 41 points, along with six rebounds, two steals, two assists, two blocks, and led the Bulls to a 130–124 victory over the
Golden State Warriors. He became only the third Bulls player in history to score at least 40 points being 21 years old or younger, the other two being Michael Jordan and
Elton Brand. Moreover, he matched
Linas Kleiza's second-highest scoring performance for a Lithuanian player in the NBA and was just one point away from
Domantas Sabonis' all-time scoring record of 42 points. ==National team career==