With training camps opening this week, the offseason is almost over. And so is our “Best Offseason Pickups” series, with this being the final installment. In Part I, we looked at former head coaches taking on new roles as positional assistants. In Part II, we examined players who left their teams in free agency but stayed within the division. In Part III, we studied the offseason’s most impactful one-year contracts.

Now we wrap things up by breaking down the best Day Three draft picks. These rookies don’t get as much pub as the players picked ahead of them in prime time, but each of the players below has a chance to make a significant impact this season and beyond.

1. OL T.J. Clemmings (Minnesota Vikings, Fourth Round)

Clemmings was originally projected as a first-round pick until he struggled at the Senior Bowl and was diagnosed with a stress fracture in his foot at the NFL Combine. There is still a lot of upside here, though, as Clemmings only spent two seasons on the offensive line after beginning his college career as a defensive tackle. He has excellent strength and good feet for his size (6’5”, 309 lbs.), giving him the ability to play tackle or guard.

Clemmings spent OTAs working at guard and is still a candidate for playing time on the inside. However, the Vikings have since moved him back to tackle, where he will serve as the primary backup behind LT Matt Kalil and RT Phil Loadholt. Given how poorly Kalil played last season, it may be only a matter of time until Clemmings cracks the starting lineup.

“He’s another young, developing offensive lineman that has an awful lot of good skills,” said Vikings head coach Mike Zimmer. “He didn’t even know he was hurt, and I don’t think he is hurt.”

2. WR Vince Mayle (Cleveland Browns, Fourth Round) 

The Browns are hurting for pass catchers, especially after losing Josh Gordon (suspension) and Jordan Cameron (free agency). But they found great value in Mayle, who last season caught 106 passes for 1,483 yards and nine touchdowns. Many were quick to dismiss those numbers as a product of Mike Leach’s spread offense, but the skills Mayle displayed while posting those numbers — good size, consistent hands, rapid acceleration, precise routes — all translate to the pro level.

Mayle (6’2, 224 lbs.) has been studying game film of other big, physical receivers and is trying to incorporate aspects of their game into his own.

“I watch Demaryius Thomas and Andre Johnson a lot,” Mayle told Football Insiders earlier this offseason. “[Andre] plays full speed in his routes and never changes his gears. He catches the ball, he attacks it, and he gets upfield after he catches the ball. And he’s physical. He’s a physical blocker and that’s something I want to add to my game.”

3. DE Marcus Hardison (Cincinnati Bengals, Fourth Round) 

The Bengals finished with the fewest sacks in the league in 2014 … that won’t happen again this season. One reason for that is the addition of Hardison, a tenacious interior pass rusher who posted 10 sacks and 15 TFLs as a senior at Arizona State. Although he leaves something to be desired in run defense, he is the ideal fit as a three-technique tackle in Paul Guenther’s defense.

Things are looking up for Cincinnati’s defensive front seven. Geno Atkins is now nearly two years removed from ACL surgery and has regained his explosiveness; Michael Johnson returned as a free agent after spending a year in Tampa Bay; and now Hardison has come aboard to wreak havoc on second and third downs.

Life just got more difficult for Ben Roethlisberger, Joe Flacco and whoever is sober enough to play quarterback for the Browns.

4. RB David Cobb (Tennessee Titans, Fifth Round) 

This is one of those pairings that worked out exceptionally well for both the team and the player. The Titans found great value in Cobb, who last season carried 314 times for 1,626 yards (5.2 ypc) and 13 touchdowns. And Cobb gets a chance to battle for a starting job right out of the gates, as he will compete for snaps with the underwhelming Bishop Sankey.

Cobb is a powerful, decisive runner who breaks tackles and falls forward after contact. That will be a nice change of pace from Sankey, who spent much of his rookie season dancing behind the line of scrimmage. Cobb was slowed by a hamstring injury during OTAs and mini camp, which may hinder his progress to an extent, but it is likely he takes over as Tennessee’s starting running back by midseason at the latest.

5. OLB Kyle Emanuel (San Diego Chargers, Fifth Round) 

The Chargers are embracing a youth movement at outside linebacker. Each of the top four players on the depth chart has been drafted within the last four years: Melvin Ingram (2012), Tourek Williams (2013), Jeremiah Attaochu (2014) and now Emanuel.

Emanuel was available this late because teams discounted his production due to the level of competition he faced. But it is tough to ignore the 19.5 sacks he posted as a senior, no matter the level of competition. Also, it should be noted that in eight career games against top-25 opponents, Emanuel posted 10 sacks and 16.5 TFLs.

“We’re just excited that San Diego took a chance on Kyle from North Dakota State and we know he’ll represent his family and our university exceptionally well,” said NDSU head coach Chris Klieman. “We’re going to hear a lot from Kyle Emanuel throughout his career in the NFL.”

6. DT Christian Covington (Houston Texans, Sixth Round) 

The Texans went local with their sixth-round pick, selecting Rice’s Covington. The only reason the powerful defensive tackle was available this late in the draft is he missed much of his senior season with a dislocated knee cap. But he is healthy now and joins a loaded Houston front seven that also includes J.J. Watt, Jadeveon Clowney, Vince Wilfork, Louis Nix, Whitney Mercilus and Brian Cushing.

Covington, who recorded 13 sacks and 28 TFLs during his college career, figures to play in obvious passing situations when Wilfork and Nix come off the field. He demonstrates the necessary leverage and athleticism to make a large contribution in that capacity.

Want to talk more about these and other offseason acquisitions? Join Michael Lombardo for his weekly NFL Chat on Friday at 2pm EST. But you don’t have to wait until then … you can ask your question now!