The Sports Xchange

SANTA CLARA, Calif. — Retirements hit the San Francisco 49ers’ defense hard earlier this off-season. Now another retirement has taken a bite out of the offense.

Offensive tackle Anthony Davis informed the team Friday that he plans to take “a year or so away from the NFL,” a statement the 49ers took to mean he’s retiring.

Davis, who missed four games last season due to a concussion, informed the organization he’s serious about stepping away. Reportedly, he even agreed to give back $6.5 million in signing bonuses.

The 25-year-old issued a written statement, which read, in part:

“After a few years of thought, I’ve decided it will be best for me to take a year or so away from the NFL. This will be a time for me to allow my brain and body a chance to heal. I know many won’t understand my decision; that’s OK. … I’m simply doing what’s best for my body as well as my mental health at this time in my life.”

49ers general manager Trent Baalke responded a bit coldly to the announcement, saying, “The 49ers’ organization thanks Anthony for his contributions to our team over the last five seasons and wishes him the best as he moves on from the game.”

Coach Jim Tomsula said he wasn’t surprised by the news, noting that he recognized Davis needed time to make up his mind what he wanted to do, much as defensive end Justin Smith had done before announcing his retirement last month.

Linebackers Patrick Willis and Chris Borland also have retired this offseason.

The 49ers are expected to move Erik Pears, an off-season free-agent signing, into Davis’ spot. Pears played right guard for the Buffalo Bills last season after having spent a majority of his NFL career as a tackle.

–The media spent much of its time during the open portion of the 49ers’ ongoing voluntary offseason workouts studying quarterback Colin Kaepernick, trying to figure out any tinkering to his mechanics he might have made since the end of last season.

The most obvious observation: He’s standing with his feet farther apart and taking a shorter stride in his throws.

The more compact delivery is designed to help his accuracy.

Kaepernick recorded a career-worst 10 interceptions last season and had the second-worst completion percentage in his three seasons as a starter at 60.5.

–Fullback Bruce Miller attended his first offseason team workout June 5 after having pleaded no contest to a charge of disturbing the peace, a misdemeanor, earlier in the week.

Miller had been arrested following a public outburst at a mall involving his wife and her cell phone.

Miller agreed to 16 weeks of counseling as part of his agreement with the court.

–First-round pick Arik Armstead, a defensive end from Oregon taken with the No. 17 pick in the first round, was the only 2015 draft choice not at the workouts June 3-5. He had no choice.

By rule, rookies who were picked in the draft are not allowed to participate in organized team workouts until finals are over at their school.

The University of Oregon, where Armstread starred last season, doesn’t complete its finals until June 12.

All nine of the 49ers’ other draft picks attended schools that finished finals in May.