9:25am: The Pirates have acquired Stewart in exchange for a player to be named later, the teams announced via press release.
8:56am: The Pirates will acquire catcher Chris Stewart from the Yankees, according to Ken Rosenthal of FOX Sports (on Twitter). ESPN's Buster Olney was the first to report that a trade was in the works (Twitter link). Jon Heyman of CBS Sports reported prior to the agreement that the Yankees would likely receive cash considerations or a player to be named later in the deal (also on Twitter).
Stewart, 32 in February, was a non-tender candidate after hitting .211/.293/.272 in a career-high 340 plate appearances with the Yankees in 2013. However, he's regarded as a superior defensive catcher to the Pirates' Michael McKenry, who is a non-tender candidate himself after missing the final two months of the 2013 campaign due to knee surgery.
Stewart projects to earn $1MM in arbitration, per MLBTR's Matt Swartz, while McKenry's projection sits at $900K. Either backup will likely face competition in the form of Tony Sanchez, who offers more with the bat at a slightly lower price. Pittsburgh could also carry all three into Spring Training, where the trio would compete for the right to play second fiddle to primary catcher Russell Martin.