Pie split time between Triple-A Iowa and the Cubs last season, hitting .241 in 43 games with the big club. A career .223 hitter in 130 games over the past two seasons, Pie has three home runs and 30 runs batted in at the big league level. He was named the top prospect the in Cubs' minor league system by Baseball America in 2007 and 2006.
The left-handed Olson went 9-10 with a 6.65 earned run average in 26 starts last season for the O's. He is 10-13 lifetime with a 6.87 ERA in 33 starts over two seasons.
Williamson was the Orioles' 14th round selection in the 2007 First Year Player Draft.