To understand the situation, you need to go back to the 2012 season. Phillips was going to become a free agent at the end of the season while teammate Joey Votto (first baseman for the Reds) had two years remaining on his contract. According to Phillips, Reds management talked to Votto before talking to Phillips. The result was a contract extension offer of $225 million over 10 years which Votto accepted. Then they went to Phillips and offered him a six-year deal worth $72.5 million which he accepted.
On the face of this, it looks like Votto is getting paid a lot more than Phillips. For me, to compare these salaries fairly, I need to determine the actual salaries for this year and the next two years. I found two sources for this, which agree on the base salaries: Baseball Player Salaries and Sports Contracts.
Looking at it this way, things don't look so lopsided. Also note that Votto is taking a pay cut next year; Phillips isn't. I don't know if Votto is worth $10 million more than Phillips over three years or not but I think Phillips' outrage is misplaced.