VIDEO: Manny Pacquiao's knockout singing to Justin Bieber hit in new movie

Who would have thought Manny Pacquiao would be such a huge Justin Bieber fan? Nope, us neither.

After all, teen pop superstar Bieber is a fully-fledged member of Floyd Mayweather's entourage having been a regular feature at the unbeaten Americans bouts, even carrying the fighter's belts to the ring.

Bieber took his loyalty to 'Money' one step further in 2012 when he mocked Pacquiao after his knockout defeat to Juan Manuel Marquez with a series of pictures on Instagram.

One of them included the hashtag "No Competition", implying that close friend Mayweather is the superior fighter to Pacquiao.

The posts, unsurprisingly, triggered a tidal wave of abuse from Pacquiao's loyal supporters, many of whom warned that Bieber was no longer welcome in the Philippines.

Not that Pacquiao seems to hold a grudge as the short footbage above shows the boxing idol singing along to Bieber's No1 smash hit "Baby".

"Manny"

The behind-the-scenes clip is taken from the upcoming movie about Pacquiao's life, entitled "Manny", which is due to be released later this year.

The feature length documentary, directed by Ryan Moore and Academy Award Winner Leon Gast, tells the Pacquiao's Cinderella-man story - from abject poverty to becoming an eight-weight boxing world champion, congressman and international icon.

Watch the awesome Manny Pacquiao Movie trailer, featuring Mark Wahlberg and a very bold statement from Freddie Roach, below.

The World Premiere for "Manny" will take place at the SXSW Film Festival in Austin, Texas in March.

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