The unofficial start to 2021 NFL free agency has arrived.

The "legal tampering" window opened at 12 p.m. ET Monday, and some of the top pending free agents started coming off the market even before then. The Green Bay Packers, for example, locked up running back Aaron Jones with a new four-year deal Sunday.

With the market set to officially open at 4 p.m. Wednesday, the majority of the league's high-profile free agents will likely be spoken for by week's end. Teams that strike out on premier talent may have to turn their attention to the trade market instead.

Last offseason, the Minnesota Vikings traded wideout Stefon Diggs to the Buffalo Bills after free agency had opened. Diggs went on to lead the league in both receptions and receiving yards, while Minnesota used one of the draft picks it obtained for Diggs on rookie Pro Bowler Justin Jefferson.

Could a similar blockbuster trade emerge in the coming days? Absolutely.

We've already seen teams agree to trade for Matthew Stafford, Jared Goff and Carson Wentz this offseason. More big-name players could soon change teams via trade.

Here, we'll examine seven notable trades that could still unfold, based on recent rumors, team needs and a little old-fashioned logic.

Browns Send David Njoku to Jacksonville

Cleveland Browns tight end David Njoku has yet to establish himself as an NFL star, but the 2017 first-round pick has flashed a fair bit of promise as a pass-catcher. In 2018, he racked up a career-high 639 yards and four touchdowns.

Entering the final year of his rookie deal, Njoku could soon be on the move. He asked for a trade last offseason, and the Brown also have Austin Hooper and 2020 fourth-round pick Harrison Bryant at the position.

While head coach Kevin Stefanski likes to utilize multiple tight ends in his offense, Njoku may be viewed as expendable for the right price.

The Jacksonville Jaguars, meanwhile, lack a high-end pass-catcher at tight end. Tyler Eifert led the position group with 349 receiving yards in 2020, and the Jaguars figure to use the No. 1 pick in the draft on a new franchise quarterback.

A pass-catching tight end can be a huge asset for a young signal-caller, but the free-agent market is light on such players, especially after Jonnu Smith agreed to a deal with the New England Patriots, according to ESPN's Adam Schefter. That could lead Jacksonville to the trade market, and if the Browns do view Njoku as expendable, a deal could make sense for both sides.

Eagles Trade the No. 6 Pick to the Patriots

The New England Patriots need a long-term answer at quarterback. While they recently signed Cam Newton for another go, he's more likely to be a stopgap than the future of the franchise.

That future could potentially lie in the draft, where Clemson's Trevor Lawrence, BYU's Zach Wilson, Alabama's Mac Jones, Ohio State's Justin Fields and North Dakota State's Trey Lance are all potential first-rounders. However, the Patriots won't be on the clock until the 15th pick, which could be problematic if there's an early run at the position.

If New England latches onto a specific quarterback prospect, it may look to trade up in the draft.

The Philadelphia Eagles are a prime potential trade target, as they own the sixth overall pick and—at least publicly—aren't interested in taking another signal-caller. According to ESPN's Chris Mortensen, Eagles owner Jeffrey Laurie has "instructed" his team to build around second-year quarterback Jalen Hurts rather than create a quarterback competition.

While trading up to No. 6 likely wouldn't allow the Patriots to land Lawrence or Wilson, it could net them the next quarterback on their draft board—or at least put them within reasonable trade range.

The Eagles, meanwhile, could add more draft capital with which to build around Hurts while guaranteeing that they aren't giving up the rights to a quarterback they'll face often within their own conference.

Eagles Send Zach Ertz to the Colts

If the Eagles are looking to add draft capital, tight end Zach Ertz could be part of the equation.

According to NFL Network's Tom Pelissero, Philadelphia is hoping to get a third- or fourth-round pick in a trade for Ertz, though the tight end is growing "increasingly impatient."

The Indianapolis Colts would make a ton of sense as a trade partner. The Eagles already worked out one blockbuster trade with them, sending Wentz to Indy in exchange for a 2021 third-round pick and a conditional 2022 second-rounder.

The Colts could use a quality pass-catching tight end—Mo Alie-Cox led the position group with 394 receiving yards in 2020—and Ertz could be the perfect target. He already has chemistry with Wentz and has experience playing for head coach Frank Reich.

Reich, Wentz and Ertz were together for two seasons when Reich was Philadelphia's offensive coordinator. Reuniting them in Indianapolis could be beneficial for all parties involved.

Jets Send Sam Darnold to Washington

Trevor Lawrence and Zach Wilson are widely expected to be the first two quarterbacks taken in the draft. Lawrence has seemed like a lock for the No. 1 spot for some time, although NBC Sports' Chris Simms believes Wilson is the better pro prospect.

The New York Jets own the No. 2 pick in the draft and could use it on whichever of Wilson or Lawrence falls to them. If they're leaning that way, incumbent quarterback and 2018 No. 3 overall pick Sam Darnold will likely be on the move.

"There is a market for Darnold, based on supply and demand," ESPN's Rich Cimini wrote.

Cimini noted the Washington Football Team is "desperate for a starter," which is a logical conclusion given its situation. Washington re-signed Taylor Heinicke this offseason but also parted with veteran Alex Smith. It signed Ryan Fitzpatrick, according to Schefter, but only for one year.

Washington needs to add to its quarterback room for the long-term, but it may not have a crack at one of the top prospects with the 19th pick in the draft. Albert Breer of The MMQB named Washington as a team to watch on the Darnold front, which makes sense.

Washington could land a young quarterback with upside by trading for Darnold, while New York could add to its draft capital and move Darnold outside of the conference.

Seahawks Send Russell Wilson to the Bears

The Seattle Seahawks may not actively be trying to move quarterback Russell Wilson, but there's discord between the two parties, and the team is at least been gauging his market.

"I know there's been calls made on both sides," ESPN's Dianna Russini said on The Pat McAfee Show. "Going to Seattle, and from Seattle to other teams."

The Chicago Bears are one team that is expected to go after Wilson hard in the coming weeks. ESPN's Jeremy Fowler said the following on SportsCenter:

"The expectation leaguewide is that Chicago's going to try to take a big swing here at getting Russell. Now, Seattle has given no clear indication that they are going to trade him. Russell Wilson himself still does not expect to be traded. But Chicago's going to at least try to make that change and put together a package. That's what most people around the league do expect."

There's a lot that would have to go into this potential trade. Chicago would have to produce an enticing trade package and generate the cap space it needs to add Wilson. The Bears are barely under the salary cap at the moment.

Still, if Chicago pushes hard enough and Seattle can be convinced to move Wilson, this trade could unfold during the offseason.

Ravens Send Orlando Brown Jr. to the Chiefs

Baltimore Ravens right tackle Orlando Brown Jr. filled in on the left side this past season and is looking to move there permanently. This could lead to a trade, as the Ravens have given Brown permission to seek one.

"Orlando Brown's representatives have begun exploring trade possibilities for a player eyeing a full-time role at left tackle, per source. The Ravens are aware of those plans," ESPN's Jeremy Fowler tweeted in February. "Plenty of teams will be in the market for left tackle help in coming weeks and months."

According to NFL Network's Mike Garafolo, at least six teams are interested in acquiring Brown. While he didn't name those teams, the Kansas City Chiefs would be a logical landing spot.

Kansas City recently parted with offensive tackles Eric Fisher and Mitchell Schwartz. Although the Chiefs have agreed to a deal with guard Joe Thuney, according to NFL Network's Ian Rapoport, they'd be wise to continue remaking their offensive line by adding a tackle. With $26.7 million in cap space, a deal for Brown should be financially feasible for Kansas City—he's due to carry a cap hit of $3.6 million.

A deal involving Brown could be a huge win for both teams if the Chiefs can offer a desirable trade package.

Texans Send Deshaun Watson to the Jets

The biggest potential trade we could still see this offseason involves Houston Texans quarterback Deshaun Watson. The 25-year-old three-time Pro Bowler has informed Houston that he no longer wants to play for the franchise, according to ESPN's Dan Graziano.

While the Texans have thus far been hesitant to even entertain trade offers, many around the league believe that will change as the draft draws closer.

"They sense that Houston has no reason to jump at this point," ESPN's Jeff Darlington said on The Rich Eisen Show. "There's a belief that Watson will eventually be available, that he will wind up playing for another team, but that Houston is merely trying to wait this thing out whether for leverage or public relations reasons."

If Houston is eventually willing to deal Watson, the Jets could be the perfect trade partner. They own the No. 2 pick in the draft, which gives them a shot at either Lawrence or Wilson.

Watson is an established star, but if the Texans are forced to move him, getting a premier quarterback prospect as part of the trade package would be ideal.

There should be no shortage of teams interested in acquiring Watson, but if the Texans become enamored with getting Lawrence or Wilson, a deal with New York would be the most sensible.

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