Manny Pacquiao vs. David Díaz, billed as Lethal Combination, was a professional boxing match contested on June 28, 2008, for the WBC lightweight championship.

Pacquiao came into the fight following a close bout in March 2008 split decision victory over Juan Manuel Marquez for a super featherweight title.

Diaz, the WBC champion made his last title defense by beating Pacquiao's most recent conqueror, Erik Morales, via unanimous decision in August 2007.

The bout took place at the Mandalay Bay, Las Vegas, Nevada, U.S. Pacquiao was stronger and faster than Diaz, pounding him with big punches from the first round on.

[citation needed] After the fight, Pacquiao's performance sealed his status as the best pound-for-pound fighter because of the retirement of the undefeated five-division champion Floyd Mayweather Jr. weeks prior to the fight[2][3] and put Pacquiao's name in the history books as the only Asian fighter to win five world titles in five weight classes.