Jake Gyllenhaal's amazing body transformation for his latest film role

Jake Gyllenhaal is unrecognizable again — especially from the neck down — in a brand new still from his upcoming movie.

The actor already shed 13 kilos for his role as a shady cameraman in his latest pic Nightcrawler, and now he's done a dramatic reverse body change. In the 2015 boxing drama Southpaw, Jake will star as Junior Middleweight Champion Billy "The Great" Hope, and to look the part, he packed on 7 kilos of solid muscle.

"I had him training twice a day in the boxing ring," the film's director Antoine Fuqua told Dateline. "He did two-a-days seven days a week. I pretty much had him with me and my trainer every day. I took him to almost every fight. I had him train at Floyd Mayweather’s gym in Vegas and we watched Floyd’s fights, and the Manny Pacquiao fight."

And the result of his hard labour?

"We literally turned him into a beast," Fuqua added. "Jake, my god, he’s a very electric, powerful fighter in this movie, and a guy who fights for his daughter. I’m confident that this will change how people see Jake, as a leading man."

He just earned a Independent Spirit Award Best Actor nomination for Nightcrawler, so can a shot at an Oscar be far behind? One thing's for sure, he's going to need a bigger tux this award season.

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