The Pirates designated Iwamura for assignment last Wednesday in order to clear a roster spot for third baseman Pedro Alvarez. At the time, general manager Neal Huntington said the team's first priority was to trade Iwamura so that the established infielder could hook on with another Major League club.
The Pirates were willing to pay nearly all of the remaining $4.85 million due Iwamura to do so, too.
However, the Pirates did not find any substantial interest in Iwamura and now will try to help the second baseman get back on track in the Minors.
Iwamura began the season as the team's starting second baseman before being benched in late May. He hit .182 with nine RBIs in 165 at-bats with the Pirates this year.