On the roster: Glover Quin, Tavon Wilson, Miles Killebrew, Tracy Walker (DB), Charles Washington, Rolan Milligan, Stefan McClure

Key losses: Don Carey

Making the cut: Quin, Wilson, Killebrew, Walker

On the bubble: Washington, Milligan, McClure

Best competition: Are the top five all set?

I included veteran defensive back Quandre Diggs in the cornerback preview, because that's where he's played the majority of his career, but it will be interesting to see where he lines up at the start of training camp.

Diggs finished the year at safety filling in for the injured Wilson, and played both safety and nickel cornerback in the open OTA and minicamp practices this spring. Where he lines up in training camp will have a significant impact on this position.

Quin, Wilson and Killebrew all return, and the Lions selected the versatile Walker in the third round of this year's draft.

Counting Diggs, that seems like a solid five, which is how many safeties the club kept on the initial 53-man roster out of camp last season. We'll see if any of the other names can impress enough to get into the conversation.

Twentyman's take: Over the last few years in New England, the Patriots' defense, led by now Lions head coach Matt Patricia, really valued the safety position and the use of a "big nickel" scheme with three safeties, two cornerbacks, two off the ball linebackers and four defensive linemen. It was one of many schemes the Patriots and Patricia deployed, but it was one of the more effective.

The key to running that kind of personnel group is to have versatile safeties, which the Lions do. Quin can play both safety spots. Wilson is very good stepping up in the box and stopping the run. Diggs can play the middle of the field or the slot, same with Walker, and Killebrew has the kind of size and speed that allows him to line up in a lot of different spots.

Patricia's defenses are known to be creative. The talent, depth and versatility the Lions have at the safety position should allow Patricia and defensive coordinator Paul Pasqualoni to have different options when it comes to personnel groupings in the back end of the defense. This is a pretty experienced and versatile group of safeties in Detroit.

By the numbers:

8: Interceptions recorded by Lions safeties last season (Quin, 3; Diggs, 3; Wilson, 1; Killebrew, 1)

2,066: Total number of yards after the catch allowed by the Lions' defense in 2017, which was the second most in the NFL.

68.7: Opponent passer rating last season on attempts of at least 21 yards in the air. The Lions ranked 11th in the league.

26.1: The third-down percentage in the red zone for opponents against the Lions' defense last season, which was the second lowest in the NFL.

Quotable: "I think in this day and age, with the offenses being what they are, with the slot receiver being a big-time guy, with running backs being like Marshall Faulk and Reggie Bush, those type of running backs being able to come out of the backfield, I think position flex(ibility) is where you have to be," defensive backs coach Brian Stewart said this offseason.

"You have to be sturdy enough to be able to tackle… and then you also have to be athletic enough to be able to cover them downfield. Position flex is big nowadays."