The Detroit Lions have spent the past year building one of the best defensive lines in football, and they're not done yet.

The Lions agreed to a one-year deal Friday with free-agent defensive tackle Mike Daniels, who was released earlier this week by the Green Bay Packers.

The deal is worth up to $9.1 million, with $7.8 million guaranteed.

Daniels missed six games last season with a foot injury and tied his career-low with two sacks, but the 30-year-old was one of the best interior linemen in the NFL at the height of his career, making the Pro Bowl in 2017.

The Lions released veteran running back Theo Riddick on Saturday to make room for Daniels.

Daniels adds depth and experience to an already deep defensive line.

The Lions signed defensive end Trey Flowers as a free agent this spring, added nose tackle Damon Harrison in a trade with the New York Giants last fall and return Da'Shawn Hand, A'Shawn Robinson and Romeo Okwara from a team that ranked 10th against the run last season.

Harrison is currently on the non-football injury list after skipping offseason workouts in a contract dispute, and Robinson has missed the first two days of camp for personal reasons.

The Lions struggled up front early last season, but blossomed after acquiring Harrison for a fifth-round pick.

This fall, they should be even stronger with a year of seasoning in coach Matt Patricia's defense and more depth at every position on the line.

"I’m always optimistic," defensive coordinator Paul Pasqualoni said earlier this week when asked how good his defensive line can be. "For me, it’s exciting to have the guys we have up front. So I’m not going to make any predictions, but our goal is to be as fundamentally-sound, as technique-aware and good as we can possibly be and hopefully make a bunch of tackles with the defensive line. That’ll make the coaches very, very happy, and I think the fans will be very happy, too."

Daniels played seven seasons for the Packers and and helped the team win four NFC North championships. He had missed just four games in his career before last season, had five straight years with four or more sacks, and was released in part because of a $10.7 million cap number.

The Lions entered Friday with nearly $23 million in cap space, according to NFLPA records.