The 32-year-old, who captured the WBC title against Marco Huck (40-3-1) last April in Germany, booked his place in the semi-final for a unification with Oleksandr Usyk early next year.
Following a messy twelve round affair, Briedis took a 116-110, 115-111, 114-112 verdict from the former heavyweight contender.
Based in Cork, Ireland, where he defected to from Cuba, Perez, 31, lost for the third time in his career but the first at the cruiserweight limit.
Perez proved he does belong at world class in the lower division though and can come back in the future.
In the co-featured event, former WBO Cruiiserweight World Champion Krzysztof Glowacki (28-1, 18 KOs) proved too tough for Leonardo Bruzzese (18-4, 6 KOs) as he took out the Italian-Argentinian in the fifth round.
Glowacki is a reserve on the WBSS shortlist and would be in line to step in should one of the current competitors drop out for any reason.
World Boxing Super Series cruiserweight results / fixtures:
Sept. 9 – Cruiserweight Quarter-Final in Berlin, Germany
Oleksandr Usyk (13-0, 11 KOs), Kiev, Ukraine
WTKO10
Marco Huck (40-5-1, 27 KOs), Berlin, Germany
(Usyk retained WBO cruiserweight title)
Sept. 23 – Cruiserweight Quarter-Final in San Antonio, Texas, USA
Yunier Dorticos (21-0, 20 KOs), Miami, Florida, USA by way of Cuba
WKO2.
Dmitry Kudryashov (21-1, 21 KOs), Challenger, Volgodonsk, Russia
(Dorticos retained WBA cruiserweight title)
Sept. 30 – Cruiserweight Quarter-Final in Riga, Latvia
Mairis Briedis (22-0, 18 KOs), Champion, Riga, Latvia (Retained WBC title)
WUD
Mike Perez (22-2-1, 14 KOs), Challenger, Cork, Ireland by way of Cuba
Oct 1 – Cruiserweight Quarter-Final in Newark, New Jersey, USA
Murat Gassiev (24-0, 17 KO’s), IBF champion, Russia
Krzysztof Wlodarczyk (53-3-1, 37 KO’s), Challenger, Poland
Semi-Finals
Olesandr Usyk v Mairis Briedis
Yunier Dortios v Gassiev / Wlodarczyk
