It was also his second tour title after his win in Montpellier in 2022.
Bublik, ranked 48th in the world, shot out of the blocks and snatched a break on Rublev's very first service game to move 2-0 up.
With his booming serve proving impenetrable for his opponent Bublik quickly bagged the first set.
Rublev, playing in his second Halle final in three years and looking to add to his Monte-Carlo title this season, got his revenge when he managed to convert his third break point of the match at 3-2.
![Alexander Bublik in action during the final match against Andrey Rublev Alexander Bublik in action during the final match against Andrey Rublev](https://livesport-ott-images.ssl.cdn.cra.cz/r900xfq60/d953154c-c352-4ce1-be73-df6a93d7227d.jpg)
He held serve to level but Bublik recovered and went a break up thanks to a superb backhand crosscourt winner at the start of the third set.
The Kazakh, who is no stranger to grass with two finals in Newport, did serve a dozen double faults throughout the match but finished it off in style, firing a second serve ace on his first match point to land his second tour title.