Spring practice is nearly over across the ACC. Four more teams hold their spring games this weekend, leaving Virginia Tech as the last team practicing. Here is a quick look at what we learned, and what still needs work over the summer. All times are ET.

Georgia Tech (Friday, 7 p.m.)

What we learned: Georgia Tech is optimistic it will be much improved defensively, particularly up front. Not only do Freshman All-American KeShun Freeman and All-ACC second-team tackle Adam Gotsis return, but Jabari Hunt-Days has moved from rush end to tackle and has had a productive spring. The Jackets relied heavily on turnovers to bail them out last season, so now they are hoping they can continue to be optimistic while also being better against the run and on third down.

What's still missing: Injuries hit this team particularly hard on the offensive line, so there still is no clear idea who is going to be in the starting lineup when fall practice opens. Meanwhile, depth must be developed at A-back and B-back once the freshmen arrive on campus. A-back Broderick Snoddy missed spring while recovering from a leg injury, so his return will be huge. The Jackets also got a blow at B-back when Quaide Weimerskirch hurt his foot last week. His status is uncertain for the season.

Louisville (Friday, 7 p.m.)

What we learned: Concerns in the secondary have eased just a bit now that coaches have gotten a good look at what they have to work with in the fall. Leading the charge is safety Josh Harvey-Clemons, the Georgia transfer eligible to play this season. Harvey-Clemons has been impressive this spring, grabbing interceptions in the team's first two scrimmages. Defensive coordinator Todd Grantham has also been pleased with cornerback Trumaine Washington and safety Chucky Williams.

What's still missing: Louisville still has question marks at rush end and receiver, where five of the top-six pass-catchers from a year ago are gone. Transfers Jamari Staples (UAB), Ja'Quay Williams (Texas A&M) and junior James Quick find themselves leading the group, but somebody has to step up and prove to be consistent and reliable. Quarterback remains unsettled, too. Though Reggie Bonnafon has had the best spring, coach Bobby Petrino said he is in no rush to name his starter.

Pitt (Saturday, 1 p.m.)

What we learned: Pitt has been in need of a complementary playmaker opposite Tyler Boyd. Several candidates emerged this spring. Dontez Ford and Elijah Zeise have impressed the coaches, and are in line to take on bigger roles. Running back James Conner remains the centerpiece of the offense, but he will now be more involved in the pass game so his workload has increased. New offensive coordinator Jim Chaney isn't going to be afraid to go hurry-up, either.

What's still missing: Depth remains a concern on defense, where the entire unit is being asked to play more physically and aggressively under new coach Pat Narduzzi. Positions remain up in the air at linebacker and in the secondary, where Reggie Mitchell has been used as a jack of all trades. Nobody is quite sure yet where he will end up. Narduzzi also wants more production from the interior of his line, where Tyrique Jarrett has opened some eyes. How good this group can be remains to be seen.

Virginia (Saturday, 6 p.m.)

What we learned: The starting running back job doesn't necessary belong to Smoke Mizzell. Coaches have said Daniel Hamm has had the best spring among the running backs, though Mizzell returns with the most experience. Micah Kiser and Zach Bradshaw seem primed to take the reigns at linebacker; Maurice Canady has moved from cornerback to safety, replacing Anthony Harris. That has a healthy Demetrious Nicholson playing with the starters at corner.

What's still missing: Depth at linebacker has been severely tested, especially with several injuries at the position group. Kiser is not expected to play in the spring game, and freshman early enrollee C.J. Stalker has been banged up, too. How this group will make up for the production of Max Valles, Henry Coley and Daquan Romero (combined 217 tackles, 19 sacks, 33 tackles for loss) remains to be seen. For the majority of spring, Virginia had four true linebackers to work with. The offensive line hasn't been 100 percent healthy, either.