Former Penn State defensive end Anthony Zettel officially announced he’s retiring from football.

After embarking on his sixth career training camp cycle and his second for the San Francisco 49ers, Zettel said he no longer possessed the passion and energy necessary to compete at the professional level.

“Today, I share the bittersweet news that after much deliberation and reflection, I have decided to walk away from the sport that has given me so much over the years,” Zettel said in a heartfelt letter.

The former first-team All-Big Ten selection entered the league in 2016 as a sixth-round selection by the Detroit Lions. As a rookie, the disruptive edge rusher recorded 13 total tackles, including his first career sack.

His breakout season occurred during his second year with Detroit when he started all 16 games for the Lions. The Michigan native’s production more than tripled, helping him post 43 tackles, 6.5 sacks, 11 tackles for loss, and 16 quarterback hits.

Despite his monstrous output, the Lions waived Zettel the following offseason largely due to lingering injuries. In just a short amount of time on the free-agent market, he was picked up by the Cleveland Browns entering the 2018 season.

With the Browns, Zettel found his place as a reserve behind Emmanuel Ogbah and Myles Garrett, where he tallied 14 tackles and three hits for a loss in 15 games of action. Following the season, the Browns decided to retool their defense and parted ways with the once-starter, leading to another stint of free agency.

In his final three seasons, Zettel recorded 12 total tackles for the Bengals, 49ers, and Saints. Although his production steadily declined, the Penn Stater reached the Super Bowl as a member of the 49ers during his first stint with the team in 2019.

Before rejoining the 49ers organization in July, Zettel last played in the NFL as a practice squad member of the Minnesota Vikings in 2020, but did not see any action with the team.

Prior to reaching the NFL, Zettel played five years under three different coaching staffs for the Nittany Lions. His most productive season occurred as a redshirt junior in 2014 when he piled up 17 tackles for loss, eight sacks, and three highlight-reel interceptions, including one returned for a touchdown against Ohio State.

His play helped Penn State maintain the No. 1 total defense in the Big Ten throughout the 2014 season, and it even earned him first-team All-Big Ten honors alongside Ohio State’s Joey Bosa. In 2015, Zettel was one of six players to leave Happy Valley as the last set of recruits who began their careers under Joe Paterno.