By Jake Donovan

Gennady Golovkin and Marco Antonio Rubio are both well within schedule to make weight ahead of their middleweight title fight showdown, October 18 at StubHub Center in Carson, California. 

Both fighters were required to check in at the 30-day mark, as per the terms of the World Boxing Council (WBC), as Rubio is the organization's recognized interim titlist. Golovkin tipped the scales at 165 lb; Rubio checked in at 174.5 lb. 

The maximum limit for the 30-day point is 176 lb., or 10% over the limit of the weight class for which the title is at stake. 

A 7-day weight check will also be required, whether neither fighter can weigh more than 168 lb., or 5% over the middleweight limit. 

Golovkin (30-0, 27KOs) comes in as the recognized World Boxing Association (WBA) champ, attempting the 12th defense of the belt he acquired more than four years ago. The unbeaten rising star from Kazazkhstan fights for the 6th time in the United States, though making his West Coast debut with this bout.

The location is a bit closer to his adopted home, as the 32-year old regularly trains out of Big Bear, California. All of his stateside appearances have aired live on HBO, which also televises the Oct. 18 headliner. His most recent win came in July, stopping former titlist Daniel Geale inside of three rounds. 

Rubio (59-6-1, 51KOs) settled for an interim title earlier this year after waiting out an overdue mandatory title shot at Sergio Martinez. The veteran knockout artist from Mexico agreed to step aside to allow Miguel Cotto to challenge for—and win—the title this past June.

A six-fight win streak accompanies Rubio, including a 10th round stoppage of Domenico Spada this past April. His last loss came in Feb. '12, dropping a 12-round decision to Julio Cesar Chavez Jr. in a bout best remembered for its controversial aftermath. The lack of post-fight drug-testing - or random drug testing of any kind, as per the terms of a contract - forced the WBC to reinstate Rubio as its mandatory challenger, in lieu of going to court over the matter.

Rubio also came up short in a Feb. '09 title bid, suffering a 9th round knockout versus then-lineal champion Kelly Pavlik. 

The winner will be recognized as the mandatory challenger to Cotto, though the exact timeline for when such a fight will have to take place has yet to be decided. 

Jake Donovan is the Managing Editor of BoxingScene.com, as well as a member of the Transnational Boxing Ratings Board and the Boxing Writers Association of America. Twitter: @JakeNDaBox