If Deron Williams doesn't come, who does?

The leading question about the Dallas Mavericks heading into Sunday's start of free agency is, if not Deron Williams, then who?

Well, it's a fine question. In fact, if the Mavs lose out on Williams to the Brooklyn Nets, they could very well be on full alert for a starting and backup point guard. Jason Kidd, also a free agent on Sunday, has spent a lot of time talking about playing with Williams in Dallas or Brooklyn. Kidd led the Nets to two Finals appearances a decade ago and has an affection for New York. He's also talked highly about the club's prospects as it moves to Brooklyn under Russian billionaire owner Mikhail Prokhorov.

So not only could the Mavs be in line to miss out on one of the league's elite point guards, they could also lose their starting point guard from the last four-plus seasons.

In Thursday's draft, the Mavs could certainly pull the trigger on North Carolina point guard Kendall Marshall if he's available when Dallas picks at No. 17. And while trades are always a possibility, the Mavs will look to replenish the point guard position, to whatever extent, in the free-agent market.

The free agent market isn't dripping with game-changers at the point. Here's the top contenders:

Steve Nash, Suns -- The former Mav is 38 and still truckin' at an elite level. He has said he's interested in a multiyear deal and he wants fair market value, no discounts.

Goran Dragic, Rockets -- Stands to get a significant raise from his $2.1 million salary. Broke out last season, his fourth, after Kyle Lowry's injury. Rockets will want to re-sign him.

Andre Miller, Nuggets -- Seems like he's been underrated his entire career, but now at 36 he'd serve as a relatively inexpensive stop-gap in Dallas. Has been reported that Denver wants him back.

Kirk Hinrich, Hawks -- His better days are well behind him. Picking him up as backup would be far more palatable than settling on him as your starter.

Chauncey Billups, Clippers -- One of the most respected players in the league, he's getting long in the tooth and is coming off that awful Achilles' injury. Clips reportedly want him back.

Ramon Sessions -- Turns out he wasn't the Lakers' savior. Sessions has opted out of his deal to test free agency. His playoff performance certainly won't encourage teams to break the bank.