Boxing: China's Zou notches up second unconvincing win

China's great boxing hope Zou Shiming notched up an unconvincing second professional victory against Mexico's Jesus Ortega on Saturday, failing to answer questions about his lack of punching power.

The two-time Olympic gold medallist, topping the bill at Macau's Venetian resort-hotel, went the six-round distance but tired well before the bout ended, resorting throughout the final three minutes to clinging on to his equally as inexperienced opponent.

With millions expected to have tuned in to watch the nation's boxing icon on China's state television, much was riding on the shoulders of what many hope will become the country's first world champion.

In front of an electric crowd buoyed by two earlier 12-round toe-to-toe bouts, 32-year-old Zou came out technically proficient for the first three rounds, but failed to rattle the Mexican in his fifth professional fight.

Ortega largely shrugged off Zou's combinations in the first two rounds, showboating in the second and dropping his guard, only to receive minimal punishment.

In the third Zou ramped up the pressure with a slew of combinations, but soon tired, grabbing at his opponent by the fifth and spending much of the final round alternating between clinging on and trading flailing punches.

Despite the performance judges handed Zou a unanimous victory, scoring it 59-55, 59-55, 59-55.

The exhibition is unlikely to impress his legendary trainer Freddie Roach, who earlier this week described Zou's debut performance against Mexico's Eleazar Valenzuela as "playing around".