Britain’s Powell put in a powerful efficiency to cease Sweden’s Albrektsson within the second spherical.
After a quiet first spherical the place Albrektsson managed the vast majority of the motion in opposition to the cage, Powell unleashed within the second.
Powell broke free from Albrektsson’s grappling try and landed three elbows to knock down his opponent earlier than the referee stopped the competition.
Carlos Jr and Powell will struggle on 27 June on the Wintrust Enviornment in Chicago, Illinois.
The knockout format of the PFL match is in contrast to earlier years the place the primary spherical contributed to a division league desk.
The eventual champions will obtain £395,000 ($500,000) in prize cash.
Different Britons within the semi-finals embrace Fabian Edwards, who stopped American Impa Kasanganay within the second spherical of their middleweight contest final month.
Edwards will face American Josh Silveira subsequent, additionally on 27 June.
On the identical card, fellow Briton Alfie Davis faces American Brent Primus within the light-weight semi-finals after he knocked out American Clay Collard in April.
Within the bantamweight semi-finals, Briton Jake Hadley faces Brazil’s Marcirley Alves on 20 June in Kansas.
Hadley reached the final 4 by submitting Brazil’s Matheus Mattos within the third spherical of their contest in April.
