Mission Impossible: Go ahead, Nets, repair a disastrous offseason that has cost starters Kenyon Martin and Kerry Kittles while leaving Jason Kidd furious and hoping for a trade.

That is the Nets’ sorry situation, so this week, they hope to take some remedial steps by signing two free agents, forward Eric Williams and guard Ron Mercer, while starting serious discussions with Richard Jefferson about a contract extension.

Sources said the Nets are prepared to offer Jefferson a max contract to avoid another Martin fiasco. Teams can talk about extensions starting today.

“We’re preparing to talk in the next few days,” said Nets GM Ed Stefanski, who declined to discuss any particulars. “We intend to talk to both RJ and Jason Collins, and we’ll go from there.”

Collins also can become a restricted free agent next summer and may have to wait, as did Martin, depending on what the Nets offer and what his camp seeks.

Extending Jefferson for six years and $84 million may be one way to placate Kidd, who returned from vacation for a stormy meeting with prospective owner Bruce Ratner and CEO Rod Thorn Friday. Kidd stopped short of demanding a trade but made it clear he does not want to be in New Jersey under present conditions.

“He’s very upset, obviously,” one source said. “He doesn’t feel good about what’s happened and if they can’t show him they’ll be competitive, he wants out and might demand a trade. This is not what he signed on for.”

Another source echoed the sentiments about Kidd’s anger and said the All-Star agreed to a cooling off period and a wait-and-see approach. Complicating matters is Kidd’s health: he’s coming off microfracture knee surgery,l so his value is ridiculously low.

When the Nets shopped Kidd hoping to keep Martin, teams immediately expressed concerns about the knee. What the Nets get for Kidd now might make it seem like they swindled the Nuggets and Clippers in those Martin and Kittles disasters that were mandated by Ratner.

The Brooklyn developer apparently has listened to some investors who advised Napoleon invading Russia was a good idea. They have stayed in the shadows and Ratner has been blistered. Hey, he’s out front.

To try to compensate, the Nets likely will land Williams, a 6-8 forward who defends and can hit a three, plus Mercer, who was released by the Spurs last season. Williams would get a three-year deal worth $11.5 million while Mercer would get two years for $3.3M.