Born in 1999, Hazer is 1.91 meters tall and plays as a guard.

He developed through the youth system of Banvit and began his professional career in 2015 with Bandırma Kırmızı. After two seasons there, he joined Banvit’s senior team. In the 2020-21 season, he went to Beşiktaş Fibabanka, and a year later, moved to Fenerbahçe Beko. Ahead of the 2024-25 season, Hazer joined Bahçeşehir Koleji and completed the season with them.

Şehmus Hazer has celebrated two Turkish Basketball Super League championships in the 2021-22 and 2023-24 seasons, along with winning the Turkish Cup in 2024.

He has represented Turkey at the U16, U18, and U20 levels and played for the senior national team at the 2022 European Basketball Championship.

This season in the EuroCup, Hazer played 21 games, averaging 23:10 minutes per game with 9.6 points, 2.2 rebounds, and 3.0 assists.

In the Turkish Basketball Super League, he appeared in 33 games, averaging 22:19 minutes with 10.7 points, 2.5 rebounds, and 2.6 assists per game.