After a successful career in Europe, Mejri was the first (and only) Tunisian NBA player when he joined the Dallas Mavericks in 2015 as a 29-year-old rookie.

[11] On March 20, he recorded 13 points, 14 rebounds and 6 blocks in 32 minutes off the bench in a 132–120 overtime win over the Portland Trail Blazers.

[12] During his rookie season, he received multiple assignments to the Texas Legends, the Mavericks' D-League affiliate.

[18] On October 10, 2019, Mejri returned to Spanish EuroLeague club Real Madrid for the rest of the season.

[22] On September 16, 2021, Mejri signed in Kuwait with Al-Jahra of the Kuwaiti Division I Basketball League.

[24] In March 2023, Mejri made his debut for Kazma of Kuwait in the West Asia Super League (WASL), recording 19 points and 17 rebounds in a win over Shabab Al Ahli.

[27] In 2011, Mejri was named MVP, as Tunisia won the 2011 FIBA Africa Championship, and received an invitation to the 2012 Summer Olympics in London.