Jake Arrieta is baring it all…

The 30-year-old part-Puerto Rican baseball star appears in only his birthday suit in ESPN The Magazine‘s eighth annual The Body Issue.

The Chicago Cubs ace dropped trou for photographer Marcus Eriksson for the special issue, in which the world’s top athletes take off all their clothes and pose for photographs that help celebrate the athletic form.

Arrieta, a Cy Young Award winner who has pitched two no-hitters, is considered one of the best pitchers in baseball, appears on the cover of this year’s Body Issue.

“The offseason is where I really put my body to the test. I try and push the boundary as far as I can while still getting a decent amount of recovery time,” says Arrieta of his workout regime. “The days where I really want to tax myself and replicate late-inning situations where your legs are heavy, I’ll do about an hour of cardio beforehand, usually on a StairMaster. So I can replicate situations late in games, late in the season, where that nervous energy is at a heightened point and you have to control your emotions knowing your body is not completely where you need it. That’s where the mental mindset comes in most.

Arrieta, who trains with Pilates in the offseason and in-season on a daily basis, believes his flexibility is his No. 1 asset.

“Three years ago, the splits was something I told myself I was going to be able to do by the end of that offseason; it took me two years to actually do it,” says Arrieta. “Hamstring flexibility and hip mobility for me are the two most important factors on the field. Obviously we need to have a strong shoulder, strong scap, strong lats and a durable elbow to have longevity as a pitcher, but being durable and being mobile in the hips and flexible in the hamstrings take so much pressure and stress off of my arm. My flexibility is a huge asset.”

But Arrieta is also fit mentally, especially when he’s on the field.

“The way that you present yourself on the mound is so tremendously important. That was one of the biggest takeaways for me as a young kid from Nolan Ryan, from Roger Clemens, from Randy Johnson,” says Arrieta. “The look in their eyes that they had, whether they were a nice guy or not, they looked like they wanted to tear your head off when they took the mound. That’s the way I like to be. I expect to win, I expect to beat everybody I play. It’s kind of that quiet confidence that I have inside that I try to present to the opponent without getting too overboard. Because there are times when I seem composed but inside I’m losing my mind.”