The Suns? proposed trade of Quentin Richardson and a first-round draft pick to New York for Kurt Thomas "is losing steam," an NBA source said Monday night.

The trade is believed to be in trouble because of questions about the insurability of Richardson's contract. Richardson struggled with back problems at times when he played for the Los Angeles Clippers.

The Suns offered Richardson a six-year deal worth $43.5 million last summer, a deal the Clippers declined to match.

Under the proposed terms of the trade, the Suns also would send the Knicks a first-round pick as early as next year.

They would get Thomas, who can play both center and forward. With the Suns, he could either start at center or back up at both positions.

Thomas, who turns 33 in October, averaged a double-double for the first time this season: 11.5 points and 10.4 rebounds.

He has three years and about $22 million left on his contract.