Combat doesn’t get more combative—verbally and physically—than this.

Fightin’ words preceded the UFC Championship fightin’ now upon us as Conor McGregor (18-2) takes on Jose Aldo (25-1). Sure, McGregor called Aldo “a little weasel” in the mounting sniping in mainstream and social media, but now it’s time to put up and shut up for “The Notorious” (McGregor) and “Scarface” (Aldo) in a mixed martial arts melee that’s easily one of the year’s biggest cards.

Initially set for last July, the grudge match was postponed when Aldo, a seven-time defending champion, withdrew due to a rib injury.

Ranked No. 1 in the UFC pound-for-pound rankings, the Brazilian-born Aldo, 29, began fighting at 17, and was with World Extreme Cagefighting when it merged with the Ultimate Fighting Championship. Known for relying on the basics of Muay Thai—the combat sport from Thailand built on standup striking and clinching techniques—he often gains dominance by trapping opponents in a crucifix position.

Hailing from Dublin, Ireland, McGregor, 27, abandoned his life as a plumber at age 20 to become a mixed martial arts star in 2008 and began an undefeated streak of 14 wins in 2011. When Aldo pulled out in July, McGregor defeated No. 1-ranked contender Chad Mendes to win the interim featherweight championship.

On Dec. 12, either McGregor or Aldo will own that title, minus the “interim.”

MGM Grand, 3:30 p.m. Dec. 12, $175-$1,250 plus tax and fee (sold out). 800.745.3000 Ticketmaster