HOUSTON -- Restricted free agent Donatas Motiejunas won't report to the Houston Rockets because of a difference of nearly $6 million from the offer sheet he signed with the Brooklyn Nets, sources told ESPN on Wednesday.

Last week, Motiejunas signed a four-year, $37 million offer sheet with the Nets. The Rockets on Monday opted to match that offer. However, based on the CBA, the Rockets only had to match the principle terms of the offer sheet, which came to $31 million.

The $6 million difference was to be paid to Motiejunas via incentive clauses if he played for the Nets.

After the Rockets matched the offer sheet, Motiejunas had two days to report for his physical, which his agent B.J. Armstrong told the team he would not do.

Houston's options are to keep their first-refusal exercise notice open and wait for Motiejunas to report. If he doesn't report, Houston can pull the offer Thursday and Motiejunas would become a restricted free agent. If they don't pull the offer, it would expire automatically March 1.

Rockets officials are willing to work a separate deal with Motiejunas, something his agent is willing to talk about, in the $31 million range. One of the problems with the offer sheet for the Rockets is a $9 million guarantee for the 2017-18 season. Based on the offer sheet, a team would have to make a decision on March 1 to enact that clause. Houston, according to a source, would like to push that date to the summer.

Motiejunas, who has averaged 7.8 points and 4.0 rebounds per game over his career, has undergone two back surgeries, which has given several teams pause about his long-term health. Motiejunas told ESPN last week he passed a series of tests on his back in New York before signing the offer sheet with the Nets and should pass any physical given.

Armstrong is also open to receiving an offer sheet from another team.