The 35 year-old, who has won world titles at an unprecedented eight different weights, gave the American his full respect as Pacquiao came face-to-face with his November 22 challenger for the first time.
“Chris Algieri fought an exceptional fight in June to win the world title from Ruslan Provodnikov,” said Pacquiao.
“I am impressed and intrigued by his scientific approach to training and boxing. He may be the smartest and the fittest athlete I have ever faced and that makes him the most dangerous.
“I worked hard to reclaim my welterweight title and I will work harder to make sure I keep it on November 22.
“As always, I dedicate this fight to my fellow Filipinos around the world and to bring glory to the Philippines,” he added.
Algieri, 30, has been widely written off in the press since being announced as a surprise choice for Pacquiao during the summer and will need to put in an even better performance than against Ruslan Provodnikov to stand any chance of prevailing.
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