With the way Miles Teller gushed about his girlfriend, she must really be one lucky girl blessed with a loving boyfriend, who just showed off his amazing hot transformation.

The American actor and musician seems to be so vocal about his admiration for girlfriend Keleigh Sperry.

While in Los Angeles to promote his new movie on weekend, the Pennsylvania-born star shared new details about the model and actress, who is also his leading lady in "Insurgent."

"She's lovely.It's been pretty easy because right now, her full-time gig is kind of being with me and before her, I would never invite a girl into that world because I didn't think I could have both," he told E! News.

Miles Teller further added about his girlfriend, "She's allowed me to be able to really focus on acting and do what I want to do. She can come to set and visit me and hang out and doesn't really distract me from it."

Fans and followers of the couple get to have a glimpse of their lovely whereabouts through Keleigh Sperry's Instagram posts.

"She does have a very active Instagram account so people can see where I'm at. Probably too much. What are you going to do? I'm not going to stop traveling because she likes Instagram," the "That Awkward Moment" star shared.

Meanwhile, the "Insurgent" star may have completely veered away from former boy-next-door looks judging from his present built.

In his appearance on "The Tonight Show With Jimmy Fallon", 40-year-old host showed off before-and-after shirtless photos of the "Insurgent" star to the audience's delight as they got awed by the sight, especially that the after snap featured Miles Teller's well-sculptured physique and six-pack abs.

Accordingly, the 28-year-old's hot transformation was motivated by his role in the upcoming film "Bleed For This", a sports drama on the life of five-time World Champion Boxer Vinny Pazienza. The former "Whiplash" star will tackle the lead role of this Ben Younger film said US Magazine.