Jaime Munguia survived an almighty scare against Nikita Zon before retaining his WBA super middleweight title with a unanimous decision victory in Riyadh, Saudi Arabia.

It was fitting that the contest took place on Halloween night, with Munguia given an almighty fright by the Russian underdog. Before the opening bell, the discussion had been on how quickly the Mexican would dispose of Zon, rather than whether the fight would be competitive.

But Zon, now 12-1-1 (10 KOs), proved an awkward and dangerous opponent, coming agonisingly close to stopping Munguia in a dramatic sixth round. The champion was left reeling against the ropes, his head snapping from side to side as Zon unloaded, but the Russian could not find the finishing blow.

Zon's inexperience and the energy expended during that frantic session eventually caught up with him. Munguia took control over the second half of the contest, earning scores of 117-111 twice and 116-112 to improve to 47-2 (35 KOs).

The 34-year-old Zon had started strongly, pressing Munguia, 30, towards the ropes and unloading punches that thudded against the Mexican's guard. His unorthodox style appeared to trouble the champion, who was content to cover up in the opening rounds.

The action intensified in the third when Munguia connected with a hard overhand right. Zon absorbed the shot and responded with punches of his own before trapping Munguia against the ropes and landing a right uppercut that shook the champion.

Munguia appeared wary of Zon's power in the fourth, but gained confidence after stunning the Russian with a left hook late in the round. Another overhand right hurt Zon in the fifth, and it seemed the underdog's early resistance was beginning to crumble.

The sixth, however, almost produced one of the year's biggest upsets.

A looping left uppercut landed flush on Munguia's chin, sending him staggering backwards into the ropes. Zon immediately jumped on Munguia, unloading a succession of heavy punches that sent the Mexican's head bouncing from side to side.

A right hand crashed into Munguia's chin and left him in desperate trouble. Referee Tony Weeks watched closely as the champion struggled to defend himself, with another clean blow seemingly enough to bring an end to the contest.

But that blow never came.

Munguia somehow weathered the assault and even finished the round strongly, hurting Zon with a right hand of his own just before the bell. The Russian had come within touching distance of the WBA belt, but his had slipped away.

The pace then dropped considerably. Zon had never been beyond eight rounds and the toll of his sixth-round onslaught was beginning to show.

Munguia regained control, stepping forward behind his right hand and following with left hooks. The snap had disappeared from Zon's punches, and he could no longer force the champion back towards the ropes.

Munguia hurt the Russian to the body in the eighth, and by that stage Zon appeared to have little left in the tank.

To his credit, Zon continued to fight through the exhaustion, but he could not reproduce the success he had enjoyed earlier in the contest. Munguia pushed forwards in the closing rounds and emerged a clear winner on the scorecards after 12 rounds.

The Mexican retained his title, but his performance will surely have his fellow champions at 168lbs licking their lips.