The Major League Baseball Players' Association is upset over the lack of spending this offseason and has taken the step of filing a grievance against the Oakland Athletics, Miami Marlins, Pittsburgh Pirates and Tampa Bay Rays alleging they failed to spend their revenue sharing money.

"Teams are required to spend their revenue-sharing money to improve the on-field product, according to terms of the collective bargaining agreement, though not necessarily on their major-league payroll," writes Marc Topkin of the Tampa Bay Times.

Major League Baseball responded with a statement to the Times, saying: "We have received the grievance and believe it has no merit."

The MLBPA raised similar concerns back in 2010. That led to the Marlins signing Josh Johnson to a four-year extension worth $38 million.