The Pittsburgh Pirates made two minor trades this morning, acquiring right-hander Zach Stewart from the Red Sox for a player to be named later, as well as right-hander Vin Mazzaro and first baseman Clint Robinson from the Royals for a pair of minor-leaguer pitchers, Luis Santos and Luis Rico, per the Pittsburgh Tribune-Review.

The 26-year-old Stewart -- half of the duo sent to Boston for Kevin Youkilis -- was designated for assignment by the Red Sox last week. The right-hander made two starts for the Sox late in the year, but lasted just 5 ⅔ innings and allowed 14 runs over the two starts.

Mazzaro, also 26, has been with the Royals the past two seasons in brief stints, amassing a glaring 6.72 ERA in ten starts, making 25 appearances overall. The lefty-hitting Robinson has had success at the Royals' Triple-A affiliate the last two years, hitting .309/.396/.493 with 36 home runs and 167 RBI. The 27-year-old had his first cup of coffee with the Royals mid-season, but failed to notch a hit in four plate appearances.

Of the three players, Robinson would seem to have the highest ceiling, though that really isn't saying much.