Nathan Daniel "Nate" Robertson, (born September 3, 1977, in Wichita, Kansas) is a left-handed pitcher for the Philadelphia Phillies.
Robertson attended Wichita State University and was drafted by the Florida Marlins in the fifth round of the 1999 Major League Baseball Draft. Robertson underwent Tommy John surgery in 1998 while a sophomore at Wichita State. Robertson pitched for the Low-A Utica Blue Sox and Single-A Kane County Cougars; with the latter he was 6-1 with a 2.29 ERA in eight starts. Robertson returned to Kane County for the 2000 season but spent most of the year on the disabled list battling tendinitis in his left elbow. Florida moved him up to the High-A Brevard County Manatees, where he went 11-4 as a starter. Robertson's rise continued in 2002, as Florida promoted him to the Double-A Portland Sea Dogs of the Eastern League. At Portland Robertson amassed a 10-9 record with a 3.42 ERA, sufficient that Florida summoned him to the major league club in early September.
Robertson made his Major League debut on September 7, 2002, for the Marlins, pitching 4⅔ innings and allowing four earned runs in a 4–1 loss to the Pittsburgh Pirates at PNC Park. Robertson moved to the bullpen for the remainder of the season, making five relief appearances. The following January Florida traded Robertson along with Gary Knotts and Rob Henkel to the Detroit Tigers for Mark Redman and Jerrod Fuell.