On top of the flurry of wide receiver trades that the NFL already has seen in recent weeks, there was one more in the making.

The Steelers were in the process of trying to get a deal done for Christian Kirk, and league sources told ESPN there was a reasonable chance that the Jaguars wide receiver was going to wind up in Pittsburgh until he broke his collarbone last Sunday.

Pittsburgh's hope of upgrading its receiving corps was derailed, at least temporarily. But the Steelers are not giving up, a league source told ESPN.

The Steelers have been making calls and checking on any and all available wide receivers before Tuesday's 4 p.m. ET trade deadline, including the Jets' Mike Williams and the Panthers' Adam Thielen, according to league sources.

The Steelers will continue pushing in an attempt to improve by the deadline, but they are far from the only team looking to better position themselves for the second half of the season.

The Lions continue making calls about pass rushers, and have spoken to the Browns about former Pro Bowl defensive end Za'Darius Smith, who already has played in the NFC North for both the Packers and Vikings, according to sources.

The Falcons also have been aggressive about making pass rush calls, and are expected to purse a potential deal for Giants edge rusher Azeez Ojulari, according to sources.

The surprising Cardinals, tied for first place in the NFC West entering Sunday, also are exploring the acquisition of pass rushers such as Ojulari.

Another pass rusher who could be available is Calais Campbell, whom the Dolphins have received inquiries about, according to league sources.

If the Dolphins don't win Sunday in Buffalo, they could be more open to dealing Campbell to a contending team, according to sources.

The Saints have gotten calls about Marshon Lattimore, according to league sources. One of the potential holdups of a deal is Lattimore's health, sources said.

The four-time Pro Bowl cornerback is not playing Sunday against the Panthers, but it hasn't stopped teams from calling about him, including the two-time defending champion Chiefs.

The Chiefs already have traded for DeAndre Hopkins and Joshua Uche, but some sources around the league believe that whether it's Lattimore or another player, Kansas City could push to make another move.

The Chiefs host the Buccaneers on "Monday Night Football" and are prepared to act quickly with the trade deadline coming hours after their game.

One team that could continue trading players is the Jacksonville Jaguars, who already have traded defensive tackler Roy Robertson-Harris to the Seahawks and offensive tackle Cam Robinson to the Vikings, in addition to working on a potential trade for Kirk.

The Jaguars will continue fielding calls and entertaining offers, and other players who could draw interest include five-time Pro-Bowl guard Brandon Scherff.

The big trade this week involved the Carolina Panthers sending wide receiver Diontae Johnson to the Ravens. Johnson will make his Baltimore debut Sunday against the Broncos, but as it turns out, he already feels right at home with fellow Ravens wide receiver Nelson Agholor.

Both Agholor and Johnson are from Tampa, Florida, and have been close for years. Though they are three years apart in age, with Agholor being 31 and Johnson 28, the receivers got to know each other through youth sports during their teenage years and went to high schools on opposite sides of town.

Since then, they've remained close and train together in the offseason. After Johnson was traded to Baltimore this week, he even stayed at Agholor's house.

Now the Ravens, Chiefs, Falcons, Cardinals and others will be looking to add more players by Tuesday's deadline. What happens in Sunday's games also could help influence who is buying and who is selling, but there is expected to be one final flurry of moves ahead of the deadline.