Murkel Alejandro Dellien Velasco (born 16 September 1997) is a Bolivian tennis player.

[2] In 2021 Dellien defeated Zizou Bergs in his first Davis Cup rubber.

[4] With his brother Hugo winning the title at the 2024 Iași Open, also in Romania, the Delliens became the first brothers to win a Challenger title in the same season since the Cerúndolos in 2022.

[5] He is the younger brother of fellow tennis player Hugo Dellien.

[6] Their father, Hugo Eduardo Dellien,[7] represented Beni Department as a substitute member of the Chamber of Deputies for the Social Democratic Power alliance from 2006 to 2010.