World-class boxing is littered with "crossroad" fights－risky bouts that can quickly expose prospects as suspects or turn champs into chumps.

In the worst-case scenario, getting blown out in a crossroad match instantly relegates the loser to the fistic scrapheap ... perhaps even permanent retirement.

Think Marcos Maidana, the former world welterweight champion who was 35-4 before getting pummeled in a 2014 rematch with Floyd Mayweather Jr. He never fought again. Another example was hulking heavyweight Gerry Cooney, who was 25-0 until Larry Holmes made him kiss the canvas in 1982. Gentleman Gerry tried two brief comebacks before George Foreman sent him to permanent pasture in 1990.

Three significant crossroad bouts take place over the next few days, featuring varying degrees of difficulty.

For the legendary Manny Pacquiao, it's business as usual. For China's Lyu Bin, it's likely too much too soon. And for Zhang Zhilei, who won silver for China at the 2008 Olympics, it's probably too little, too late.

On Saturday in Kuala Lumpur, Pacquiao, the 39-year-old Filipino phenom, will attempt to wrest the WBA welterweight championship from Argentina's Lucas Matthysse.

The only eight-division world champion in ring history, Pacquiao (59-7-2, 38 KOs) has won 11 major titles and is the first boxer to capture the lineal crown in five different weight classes.

He's also the first fighter to win major world titles in four of the original eight divisions－flyweight, featherweight, lightweight and welterweight－so regardless of the outcome against Mattysse (39-4, 36 KO), Pacman's legacy as an all-time great is assured.

The more compelling storyline in Kuala Lumpur is the 12-round featured prelim, which will see Lyu attempt to become the first male boxer to capture a major world title in just his second pro fight, breaking the all-time record (three fights) held by Thailand's Saensak Muangsurin (1975) and Ukraine's Vasyl Lomachenko (2014).

Lyu, the junior flyweight gold medalist at the 2012 AIBA World Youth Championships, represented China at the 2016 Rio Olympics, where he dropped a controversial decision to Kenya's Peter Warui in the preliminary round.

The 24-year-old from Yongkang, Zhejiang province, turned pro last fall with a third-round KO of Thailand's Wanchai Nianghansa on a Beijing card co-promoted by Pacquiao－who was impressed enough to arrange Saturday's title shot against WBA junior flyweight champ Carlos Canizales (20-0-1, 16 KO).