The 49ers drafted Reuben Foster to be their "Mike" linebacker. However, he played "Will" last season to much acclaim and the loose plan for the future may be to have him stay at "Will." AP file

The 49ers wrapped up their final practice of the spring on Wednesday. Here's the detailed depth chart for the defense, which — with a couple of exceptions — will be the depth chart for their first practice of training camp on July 26. Rookies have an asterisk next to their names. For the offensive depth chart, click here.

Big end: Arik Armstead, Ronald Blair, Jullian Taylor*

Notes: This is the defensive end who lines up on the strong side — usually the left side of the defensive line — of the offense. (The strong side is where the blocking tight end lines up and the direction in which the offense likely will run the ball). Armstead is back to about 290 pounds after dropping nearly 20 pounds last year to play Leo defensive end, which is primarily a pass-rushing position. The big end must do both. Armstead also will be among those who rotate at the defensive tackle position in nickel situations.

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Nose tackle: Earl Mitchell, D.J. Jones, Niles Scott*

Notes: This position usually lines up on an angle — "shaded" — to the center and comes off the field in passing situations. Last year, for example, Mitchell played 55.3 percent of the team's defensive snaps.

Defensive tackle: DeForest Buckner, Sheldon Day, Blaine Woodson*

Notes: The 49ers were looking for a quality backup at this spot, also known as the three technique, all of last year and received a gift when Day became available late in the season. Taylor also will work here some in training camp, and this and/or big end is the future spot for fourth-round pick Kentavius Street, who will sit out this season with an ACL tear.

Leo defensive end: Solomon Thomas, Cassius Marsh, Jeremiah Attaochu

Notes: Thomas will play this spot, usually the right defensive end, on base downs. He and Buckner are the primary interior rushers on obvious passing downs. At that point, Marsh and Attaochu have entered and rushed from the edges. The team's strong-side linebackers also can be used as pass-rushing defensive ends in nickel situations.

Strong-side linebacker: Eli Harold, Dekoda Watson, Pita Taumoepenu

Notes: This player must be stout enough to hold the edge in run defense and swift enough to cover tight ends in the passing game. Harold is smart and better than expected in pass coverage and is the clear starter. The question is whether Taumoepenu, who had a late start in learning American football, can overtake the veteran Watson this season. Watson injured his calf this week but is expected to be healthy in training camp.

Middle or "Mike" linebacker. Malcolm Smith, Fred Warner*, Mark Nzeocha

Notes: The 49ers want each of their inside linebackers to be able to play the "Mike" and "Will" spots and a number of them played both in the spring. Which is to say, the best four or five inside linebackers will make the team regardless of whether they played "Will" or "Mike" this spring. The speedy Smith is best suited for "Will" or weak-side linebacker. But because the "Mike" calls the plays, runs the huddle and has more responsibility (and because Smith is the most veteran and experienced player at this position), he's been playing this spot and allowing Reuben Foster to play the more carefree "Will" role. In addition, Brock Coyle will return from a shoulder injury for the start of training camp. He started 10 games at "Mike" last season and is very strong on special teams.

Weak-side or "Will" linebacker: Reuben Foster, Korey Toomer, Elijah Lee

Notes: The 49ers drafted Foster to be their "Mike" linebacker. However, he played "Will" last season to much acclaim and the loose plan for the future may be to have him stay at "Will" and have promising rookie Warner be the "Mike." Whatever the case, Warner has a good shot at being the first inside linebacker off the bench this season, a potentially major role considering that presumed starters Smith and Foster missed a combined 23 games last season.

Outside cornerback: Richard Sherman, Ahkello Witherspoon, Jimmie Ward, Tyvis Powell, Greg Mabin, Tarvarius Moore*, Tarvarus McFadden*, C.J. Goodwin*

Notes: There's an ugly duckling in this group — Ward — who at 5-10 stands out (stands down?) in a group in which everyone else is 6-2 and 200 pounds. Witherspoon was outstanding this spring. If Sherman (Achilles) is fully healthy at the start of the regular season, he and Witherspoon are the starters with Ward being the first player off the bench if there's an injury in the secondary. (Though it's hard to see him lasting very long at strong safety). Powell was the defensive-secondary surprise of the spring. With Ward (ankle) and Sherman out, he played well with the first-string unit opposite Witherspoon. Third-round pick Moore, a college safety, also looked natural at his new position. The 49ers may have to get creative to keep all of their promising young cornerbacks. This position seemed weak when the new year league began; it appears less so today.

Nickel cornerback: K'Waun Williams, Emmanuel Moseley*

Notes: Williams is entrenched as the "starter" at this spot. He played 56.3 percent of San Francisco's defensive snaps last year. There doesn't seem to be a lot of depth here, but there is. Ward can play nickel as can fifth-round draft pick D.J. Reed.

Free safety: Adrian Colbert, D.J. Reed*, Corey Griffin*

Notes: This is Ward's best spot in the secondary and he surely would be the first player off the bench if there's an injury here. Colbert, however, is bigger, younger and perhaps more durable, which makes him a more reliable player at the spot. Reed is learning a new position and seemed to get better as the spring went on. He had a near interception of C.J. Beathard in the back of the end zone Wednesday.

Strong safety: Jaquiski Tartt, Terrell Williams Jr.*, Antone Exum Jr.

Notes: The 49ers were paper thin at this position in the spring, so much so that they signed Exum late in the period. But they will get reinforcements in July in the form of veteran Don Jones, Chanceller James, an undrafted rookie in 2017 who shined last offseason, and Marcell Harris, the team's sixth-round pick. James and Jones are returning from ACL injuries, Harris from a torn Achilles. If Tartt were to get hurt, the 49ers presumably would make a call to Eric Reid, who — surprise, surprise — remains a free agent.

This story was originally published June 14, 2018 9:58 AM.