Billy Magnussen has a good reason to get ripped.
The 28-year-old actor, who's rumored to be in the running to play Christian Grey in the big-screen version of Fifty Shades of Grey, was spotted entering the West Hollywood Equinox this morning ahead of a possible screen test for the highly coveted part.
A source tells E! News that Magnussen checked into the gym around 7:15 a.m. wearing a maroon shirt, gym shorts, running shoes, and sporting "longer, unkempt hair."
According to the insider, the blonde hottie skipped the weights and only did cardio exercises, which included running on the treadmill and doing an elliptical workout.
"He was nice, but did not interact with anyone around him," the source tells E! News. "He seemed in a rush and motivated to get his workout finished and left after only being there about an hour. He took advantage of his short time here though by putting in a lot of effort, so it seemed."
No doubt he is considering the fierce competition Magnussen's reportedly up against for the role of the erotic drama's wealthy S&M fetishist opposite Dakota Johnson's Anastasia Steele.
Others contenders mentioned include fan favorites Matt Bomer and Ian Somerhalder, Alex Pettyfer, Ryan Gosling, Scott Eastwood, Alexander Skarsgård and Robert Pattinson, the last of whom was said to be author E.L. James' first choice.
Blue-eyed hunk Charlie Hunnam originally was cast as Grey but he dropped out citing his "immersive TV schedule" on Sons of Anarchy (a source told E! News he was never truly into portraying Christian in the first place and the crush of publicity was already more than he liked).
Besides an impressive six pack, Magnussen is probably best known for his three-year run on As The World Turns, as well as stints on HBO's Boardwalk Empire and CSI.
The former soap star gained wider critical notice and a Tony nomination this past year playing Spike (and going shirtless for much of the time) opposite Sigourney Weaver and David Hyde Pierce in the Broadway play, Vanya and Sonia and Masha and Spike.
And Magnussen's stock is sure to rise even higher as he is also set to appear in the forthcoming movie adaptation of the Broadway musical Into The Woods, playing Rapunzel's Prince opposite A-Listers like Johnny Depp, Meryl Streep, Chris Pine, and Anna Kendrick.
—Reporting by Marc Malkin and Pierce Larsen