SANTA CLARA -- Cornerback Nnamdi Asomugha hasn't need much time to grow fondly of his new surroundings with the 49ers.

After two subpar seasons with the Philadelphia Eagles, Asomugha sounds as encouraged as he's ever been in his 10-year career, which started with the Raiders from 2003-2010.

"This defense fits me pretty well," Asomugha said.

How so? "There are some calls I like, and the fact the entire defense is on the same page and have been on the team for a while, it makes it easier to pick up."

Asomugha has split time at both left and right cornerback during offseason workouts, which moved into their final stage Tuesday with the start of a mandatory minicamp.

He signed a one-year, non-guaranteed contract to compete for a spot on a unit that includes all five cornerbacks from last season: starters Carlos Rogers and Tarell Brown, and reserves Chris Culliver, Perrish Cox and Tramaine Brock.

Brown, the 49ers' starter at right cornerback the past two seasons, is attending the minicamp after missing previous team activities while working out in his native Texas.

Asomugha said his mindset hasn't changed even though this is his first offseason where a roster spot is far from guaranteed.

"It doesn't change my approach. I come into every season the same way: I'm starting over. I'm still taking notes like a rookie." Asomugha hasn't had to make changes to his once-outside observations of 49ers quarterback Colin Kaepernick. "He is that guy that can throw every ball and can take off running and outrun a defense. I know the world knows that already."

For more on the 49ers, see Cam Inman's Hot Read blog at blogs.mercurynews.com/49ers. Follow him on Twitter at twitter.com/CamInman.