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Even in July, you already know your home team's rosters inside out. You followed Twitter play-by-play of minicamp seven-on-sevens all through June and have subsisted on a diet of Who Will Make the 53-Man Roster? blog speculation for weeks.

The other 31 rosters...a bit hazier. With training camp approaching, it's the time of year for scanning stories about other teams and thinking, "Holy cow, I forgot they signed that guy!"

National analysts like me, who are supposed to look at the big picture (deflated footballs, unexpected amputations, courtroom melodramas) will also easily forget some details from the transaction whirlwind of spring. For us, this is cramming season. We don't want to show up at a training camp and say, "Gee, I thought you played for the Chargers."

Here are 10 acquisitions—or groups of acquisitions, in many cases—that didn't generate much national news back in March, when all eyes were on Chip Kelly and Darrelle Revis. In a few weeks, these overlooked players will start making a big difference for their new teams.

Dwayne Harris, Wide Receiver/Returner, Giants

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The Giants did not return a single punt in their final two games last season, calling for 10 straight fair catches instead. Odell Beckham Jr. and Rueben Randle waved for five fair catches each. Both were starters at that point, and with the Giants' Final Destination-level injury tendencies, head coach Tom Coughlin was probably happy that neither tried to return a punt, ran out of bounds and impaled himself on a down marker or drowned on the Gatorade table.

Injury risks aside, the Giants haven't returned a punt for a touchdown since 2009. Harris has two punt-return touchdowns in the last three years. He's also one of the best all-around special teamers in the NFL. Harris led the Cowboys with 10 special teams tackles in 2014 and nine (with two fumble recoveries) in 2013, per NFLGSIS.com. He can help prevent those coverage lapses that cause the blood vessels in Coughlin's forehead to start throbbing.

Harris also lined up all over the formation as a wide receiver during minicamp. He is fast and elusive, so he can certainly play a role as a screen-reverse-bomb package receiver. Or he could wind up starting once the Giants' injury demon claims (or reclaims) Beckham, Victor Cruz or Randle. But drive to the local hardware store and knock on all the wood you can find, Giants fans: If the team finally catches some good health luck, Harris will bring the "return" back to punt returns, and then some.

James Casey, Fullback/H-Back, Broncos

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When you hire Gary Kubiak as head coach, you don't just hire Gary Kubiak. He comes equipped with the Kubiak custom-trim package, which includes tight end Owen Daniels, some zone-blocking offensive linemen and a fullback.

Daniels got plenty of attention when he signed with the Broncos. He drives the Kubiakmobile from city to city, and he will replace Julius Thomas as Peyton Manning's tight end.

Casey left Kubiakville for Chiplandia two years ago, joining the Eagles as a hybrid fullback and H-back after filling a similar role for Kubiak's Texans for four years. Casey is a fine run-blocker who caught 34 passes in 2012 and can still leak out of the backfield, catch a dump-off and rumble upfield for useful yardage now and then.

Casey split time with second-year tight end Joe Don Duncan at fullback in Broncos minicamp. The fact there was a fullback in Broncos minicamp is news in and of itself: Manning has worked exclusively in single-back offenses since he became Peyton Manning. Duncan is an interesting prospect—270 pounds of beef who went undrafted in 2014 due to a broken foot—but Kubiak and Manning need someone they can trust at fullback.

Casey knows the role, knows the system and will make one of the NFL's most interesting offseason transitions go a little more smoothly.

Jacob Tamme and Tony Moeaki, Tight Ends, Falcons

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It's hard to exaggerate just how bad Falcons tight end Levine Toilolo was last year. He dropped six of the 49 passes thrown to him, according to Pro Football Focus. He averaged just 7.7 yards per reception, the second-lowest average of any wide receiver or tight end in the league with 30-plus receptions.

He made up for his inadequate receiving with terrible blocking: Pro Football Focus gave him a negative-11.9 grade as a run-blocker. Matt Ryan played with the best tight end in history during his best season; last year he was stuck with one of the worst tight ends in the league.

New Falcons offensive coordinator Kyle Shanahan can live without Tony Gonzalez-level receiving chops, but a solid zone-blocking tight end is essential to his system. Moeaki, who once looked like a rising star for the Chiefs, is a quick-footed lateral run-blocker. He's also just fast enough to sneak down the field on a seamer or wheel route when covered by a slow linebacker.

You probably remember Tamme, Peyton Manning's late-career Dallas Clark surrogate. Tamme slipped to third on the Broncos' tight end depth chart last year and has just 34 receptions for 293 yards in the last two seasons. But he has also dropped just two passes in the last three seasons. He may not have another 67-catch season in him, but he won't drop a bunch of three-yard dump-offs, either.

The Falcons will get a big boost just by going from rock-bottom to around the league average at tight end. Moeaki and Tamme may be a long way from Gonzalez, but they fit the new offense and give Ryan a safety valve that's actually safe.

Sean Weatherspoon and LaMarr Woodley, Linebackers, Cardinals

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According to Darren Urban of azcardinals.com, Weatherspoon looked and sounded like his old self in Cardinals minicamp: chirping during drills, jawing at teammates, dancing and generally playing the "upbeat leader" role.

He entered the 2013 season as one of the most promising young linebackers in the league, a rangy defender for a team that nearly reached the Super Bowl in 2012. But injuries—including an Achilles tear that erased the 2014 season—and a penchant for missed tackles made him expendable for a rebuilding Falcons team.

Woodley is just 30 years old but three years past his prime. He played just six games for the Raiders last year after a long career as a Steelers pass-rushing outside linebacker. Playing out of position at defensive end, he still showed some flashes as a pass-rusher—Pro Football Focus credited him with seven hurries in limited action—but was a liability against the run before a bicep injury shut him down.

It's up to head coach Bruce Arians and new defensive coordinator James Bettcher to revitalize Weatherspoon and wring out any sacks Woodley has left in him. Bettcher was Todd Bowles' outside linebacker coach for two years and has had success with John Abraham, another aging pass-rusher. Weatherspoon replaces Larry Foote, who missed tons of tackles last season and was easy to exploit in coverage.

Weatherspoon isn't exactly Brian Urlacher as a tackler, but coverage is his game. If Bettcher can put Weatherspoon and Woodley into situations where they can excel, the Cardinals will enjoy a low-cost upgrade to both the pass rush and short-pass defense.

The Cardinals are a veteran team coming off a playoff disappointment looking for cost-effective ways to take the next step. If reclamation projects like Weatherspoon and Woodley pay off, they'll be back in the postseason. They may even bring a quarterback with them this time.

Eddie Royal, Receiver, and Alan Ball, Cornerback, Bears

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The folks at Sports Illustrated singled out Royal and Ball in an article about the most underrated additions to the NFC North a few weeks ago.

Royal joins a receiving corps that swapped Brandon Marshall for rookie Kevin White in the offseason and got just 17 catches for 140 yards from No. 3 receiver Marquess Wilson last season. Royal has been perennially undervalued since his 91-catch rookie season set unrealistic expectations in 2008. He's an excellent slot-receiving craftsman, and the Chargers essentially signed two players to replace him (more on them later).

Look for Royal to receive more targets than White, at least early in the season.

Ball has generated far less attention, in part because the Bears signed Tracy Porter and the entire Giants safety corps in an effort to fix their secondary. On the one hand, Ball is 6'2", so we are supposed to make obligatory Richard Sherman comparisons each time we mention him. On the other hand, he played for the Jaguars the past two seasons. Ball was very good in 2013 and played well last season before suffering a bicep injury. He's a capable starter who could be an even better role player.

The Bears have Kyle Fuller locked in at one cornerback position and Porter penciled in at the other. Ball fits best as a corner/safety hybrid and matchup specialist, adding depth to a Bears secondary that has been thin and talent-poor for two years.

The Bears allowed themselves to get so bad at a handful of positions that they need to stabilize their depth charts before they can seriously rebuild. Royal and Ball will solve some critical issues, allowing youngsters like White and Fuller to properly develop.

Roy Helu Jr., Running Back, Raiders

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A young quarterback like Derek Carr needs a running back who can do a little of everything: handle the ball, do something with short passes besides fall forward and pass-protect. Darren McFadden and Maurice Jones-Drew did not provide that kind of running back support last year. Helu will provide it this year.

Helu led all running backs with 11.7 yards after catch last season, according to Pro Football Focus, so he can take Carr's short passes and turn them into productive gains. PFF gave him a negative pass-protection rating, but other than two sacks allowed against the Vikings, Helu has been steady in that role for years. He has averaged 4.4 yards per carry as a change-up back for his career, so he can churn out yards when Latavius Murray needs a breather.

The Raiders also signed Trent Richardson, and perhaps Richardson will learn this year to follow the medium-sized path in front of him instead of the extra-wide one along the sideline that only exists in his mind. Richardson and Murray will compete for the starting job, with Helu dialed in to the change-up role.

When tough roster cuts have to be made in August, bank on the guy who runs/catches/blocks/plays special teams to beat the would-be superstar with baggage every time. And while Helu may not help the Raiders reach the playoffs this year, he will help Carr reach his full potential.

Stevie Johnson and Jacoby Jones, Wide Receivers, Chargers

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You remember Johnson: former Terrell Owens protege, not-quite superstar receiver with exceptional talent but a gift for pass-dropping and inconsistency. Johnson flirted with the Patriots in free agency before signing a modest three-year deal with the Chargers. It was an under-the-radar signing: After a disappointing 2013 season in Buffalo and a quiet 2014 season with the 49ers, Johnson is no longer close to an A-lister.

Johnson was actually very effective last season. He caught 70 percent of the passes thrown to him, according to Football Outsiders (35 of 50). Johnson finished 11th in the NFL in the Football Outsiders DVOA metric, which takes into account factors like third-down performance.

Johnson converted nine first downs on 13 pass targets. He had a rep for dropping perfect passes in Buffalo, but he dropped just two balls last year. He missed the final three games of 2014 with a knee injury, but he's still just 28 (29 later this month), so he's not as over the hill as you might think.

Johnson as a go-to receiver may not scare anyone anymore, but as a situational player, he can be a mismatch nightmare who either draws nickel cornerbacks in coverage or allows a niftier receiver to slide inside.

The Chargers will use him as the third receiver behind Keenan Allen and Malcom Floyd. With Antonio Gates serving a four-game performance-enhancing-drug suspension to start the year, Johnson may draw duty as the 3rd-and-medium target over the middle of the field. According to reports from minicamp, Johnson is dialed in and working well with Philip Rivers.

Johnson's presence will allow Jacoby Jones to concentrate on what he does best: returning kicks and punts. Jones now has nine career return touchdowns—10 if you count the Super Bowl—but he dropped five of the 17 passes thrown to him in 2014.

The Chargers got little out of their return game last season: Chris Davis' longest kickoff return went just 35 yards, and Keenan Allen (who is too valuable to regularly return punts) called 11 fair catches on 22 punts while sharing the job with the now-departed Eddie Royal.

Johnson may only catch another 35 passes, and Jones may be relegated to special teams, but they could take pressure off Allen so he can have the 100-catch season he is capable of. Not bad for a pair of low-cost, low-risk moves.

C.J. Mosley, Defensive Tackle, Dolphins

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Skeptical Dolphins fans could be seen grumbling on Twitter and the bottoms of message boards after the Ndamukong Suh signing: Swapping Jared Odrick and Randy Starks for Suh was actually a $114 million downgrade! There was some legitimate reason for pessimism (besides the fact major free-agent signings always seem to backfire on the Dolphins). Starks and Odrick were an effective one-two punch at defensive tackle, and while Suh is great, two big tanks in the middle are always better than one.

The Dolphins made the right move by signing Lions rotation tackle Mosley as Suh support and insurance. Mosley spent the last two seasons spelling Suh and Nick Fairley, often on running downs, and making sure there was little drop-off in effectiveness in the middle of the Lions defense.

He recorded 2.5 sacks in part-time play last year and added 16 "successful" tackles on running plays, according to the Football Outsiders Almanac. A successful tackle results in a minimal gain for the rusher. For comparison's sake, Odrick had 19 successful tackles against the run last year, Starks 17.

Mosley will be back in his rotation role this year, with Suh and Earl Mitchell (last year's rotation tackle) as the starters. That's no downgrade: Mosley is just what the Dolphins needed to let Suh be Suh.

Perrish Cox, Cornerback, Titans, and Chris Culliver, Cornerback, Redskins

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So many players left the 49ers this offseason that it was easy to lose count. If a player did not retire suddenly and spectacularly, he wasn't going to attract much media attention. Culliver and Cox were an effective young cornerback tandem for the 49ers last year, but they slipped quietly away in free agency while teammates elbowed each other out of the way so they could file their retirement paperwork first.

Culliver, now in Washington, ranked fifth in the NFL at stopping opponents' complementary wide receivers, allowing just 6.2 yards per pass attempt, according to Football Outsiders. In other words, he's a great No. 2 cornerback, and he has the chops to be a pretty good No. 1 cornerback. The Redskins still have DeAngelo Hall in their secondary, as well as Bashaud Breeland, who had a rough rookie year but did show some flashes. They should be able to mix and match their corners in a way that keeps everyone comfortable.

Cox received a lower grade than Culliver from Pro Football Focus, which credits Culliver with allowing just a 50.7 percent catch rate, as opposed to Cox's 61.5 percent. Football Outsiders' internal database revealed part of the reason for the discrepancy: Cox handled many more of the 49ers' tougher wide receiver matchups.

In Tennessee, Cox joins Jason McCourty at cornerback, with former Titans starter Blidi Wreh-Wilson (who was severely overmatched last year) competing for a nickel role. Like the Redskins, the Titans should be able to create the matchups they want, and they will benefit from the jolt of experience.

Neither Cox nor Culliver is a headline-grabbing cornerback like Darrelle Revis. But capable, still-in-their-prime starters at cornerback aren't easy to find, and for beleaguered franchises like the Redskins and Titans, a little stability in the secondary can go a long way.

Tyrod Taylor, Quarterback, Bills

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Oh sure, you know all about Taylor now, after the Bills organization spent most of June making sure everyone heard that he was the dark-horse candidate for the starting job. But when the Bills signed Taylor on March 12, just days after trading for Matt Cassel, you probably didn't notice the move at all.

Now, Bills team website reporter Chris Brown is asserting that "Taylor clearly has the strongest arm of the three QBs in the competition." (With Cassel and EJ Manuel in the mix, that just means Taylor can throw 30 yards without a running start.) Head coach Rex Ryan told Vic Carucci of the Buffalo News that he tried to trade for Taylor when he coached the Jets.

With LeSean McCoy in the backfield and Sammy Watkins and Percy Harvin headlining the receiver corps, well, 30 passing touchdowns and six more rushing touchdowns are all but guaranteed. You had better select Taylor in the third round of your fantasy draft, lest you miss out on the sleeper of the millennium.

Oops, we jumped the gun a little there. Taylor has 35 career pass attempts and 27 rushes, with all of his production coming in either mop-up situations or brief Wildcat experiments. Taylor does have a 61.6 percent completion rate, 10 touchdowns and eight interceptions, plus 453 rushing yards, on his resume—his preseason resume from 2011 through 2014. Well, there is something to be said for a quarterback who sticks as a backup for a playoff-caliber team long enough to throw 211 preseason passes.

Taylor's rise to minicamp stardom may say more about the Bills' quarterback situation than it says about Taylor. Still, his acquisition created competition, and it demonstrated an aggressive approach to solving a perennial problem in Buffalo. That's what most of these "unnoticed" acquisitions are about: finding value, assembling role players, strengthening units and maybe, just maybe, unearthing a gem.

Projecting Taylor as the next Colin Kaepernick—or even as a starter—may be a little crazy, but one of those Bills quarterbacks is going to step into a huddle with Harvin, Watkins, Shady, Charles Clay and other outstanding playmakers. Better the winner of a wild-and-wooly competition than just the incumbent first-round pick or an off-the-rack veteran journeyman.

Mike Tanier covers the NFL for Bleacher Report.