PITTSBURGH PIRATES — Recalled 3B Pedro Alvarez from Indianapolis (IL).  Designated INF Aki Iwamura for assignment.

A list of the highest paid players on each team in 2010 would include such luminous names as Alex Rodriguez, Johan Santana and Ryan Howard. Perceived underachievers like Carlos Lee, Alfonso Soriano and Barry Zito are there as well.

But Aki Iwamura?  His $4.85 million salary, which would rate in the bottom half of many teams’ rosters, topped the lowly (and low-paying) Pittsburgh Pirates, and the expectation was that the 31-year-old would recapture some of his 2008 form and anchor the young Bucs’ infield.

A .181/.292/.267 line through the first 54 games doomed that idea, and with Pedro Alvarez on the way up and Andy Laroche moving to a utility role at five years younger and 1/10 the salary, Iwamura’s roster spot became the one tabbed for Alvarez.

The Pirates, like other teams in their payroll range (only San Diego, at $37.8 million, is within $15 million of Pittsburgh’s MLB-low $34.9 opening day mark), can’t afford mistakes like this one.  But rather than compounding the error by keeping Iwamura out there, the Pirates have chosen to move Iwamura, either through a trade, or if no one claims him, back to the minors.  Teams are less willing to keep unproductive, higher-salaried players around, even bottom-10 payroll organizations like the Rays (Pat Burrell) and Nationals (Brian Bruney).