The Rockets had long since made keeping James Posey their top free-agent priority. Wednesday, they found out what he will cost, a price tag they likely will consider beyond their means.

Posey, a 6-8 forward, signed an offer sheet with the Memphis Grizzlies on Wednesday worth $24 million over four years, according to Posey's agent, Mark Bartelstein. To offer that contract, the Grizzlies would have to put together a deal worth all of their $4.9 million midlevel salary-cap exception and the largest annual raises allowed.

Because Posey, 26, is a restricted free agent, the Rockets have 15 days to match the offer to keep Posey.

General manager Carroll Dawson said the Rockets would not decide whether to match the offer until he officially receives it today and considers the team's other free-agent options.

But because the Rockets' payroll is in excess of $55 million before signing Posey and other players needed to complete the roster, keeping him likely would cost the Rockets his salary and as much money in luxury taxes, a price they are unlikely to pay. This season's luxury tax is assessed when teams' annual salaries exceed $52.9 million.

"We have to look at all the options," Dawson said. "We have two weeks. We'll have to see. We have time."