Nets trying to get Joe Johnson

The Brooklyn Nets and Hawks are engaged in ongoing talks on a multiplayer deal that would send several expiring contracts to the Atlanta for All-Star guard Joe Johnson, according to sources briefed on the discussions.

But sources told ESPN.com that the Nets have expressed concerns throughout the weekend that they're surrendering too much financial flexibility in the various trade proposals presented to date, which has the teams trying to make tweaks to push the deal through.

One big stumbling block, sources said, is Atlanta's insistence that Brooklyn include promising Nets guard MarShon Brooks in the trade to ensure that, in addition to shedding Johnson's hefty contract, it gets back at least one on-the-rise player.

Sources say that the Nets, furthermore, will only go ahead with this trade if they know that it helps convince Deron Williams -- this summer's No. 1 free agent -- to verbally commit to re-signing with Brooklyn when a league moratorium on new contracts is lifted July 11.

The most recent proposal, sources said Sunday night, would call for the Nets to send the expiring contracts of Jordan Farmar, Johan Petro, Anthony Morrow and Jordan Williams along with the signed-and-traded DeShawn Stevenson and a future first-round pick to Atlanta in exchange for Johnson.

Sources say that the Nets are insisting that the trade includes at least one of their free agents via sign-and-trade -- such as Stevenson or Gerald Green -- in hopes of keeping themselves over the salary cap. That would allow Brooklyn to keep its mid-level exception to sign an additional free agent; sources say that the Nets have serious interest in Bosnian free agent forward Mirza Teletovic to add additional frontcourt depth.

The teams are trying to work through those issues as well as the Hawks' insistence on Brooks to see if a trade can be consummated. After months of unsuccessfully chasing Orlando Magic star Dwight Howard via trade, Nets officials think the acquisition of Johnson will convince Williams to choose Brooklyn over Dallas in free agency when Williams makes his decision in the next few days.

"There's talk," one source said of the trade negotiations, "but it's not there yet."

Another source, describing the talks as "serious," added: "The Nets want Joe and they're one of the few teams that can take on his contract."