According to the DVD commentary, the scene in which Jim is hit in the face by Roy was an accident and real. David Denman (Roy) backed into John Krasinski (Jim), and hit him in the face, resulting in John bleeding. The cameras kept rolling and they kept the shot in the show. But, as a result of the injury, a photo shoot scheduled for the next day had to be canceled because John's lip was so swollen.
Actor Brian Baumgartner actually made 14 shots in a row, as revealed on the DVD commentary. Much of the basketball game was improvised.
Michael's line, "Try not to look too gay on the court", was improvised. The look on John Krasinski's face is genuine.
Phyllis volunteers to cheerlead while actress Phyllis Smith is a former cheerleader. She cheered for the St. Louis Cardinals in the 1970s.
John Krasinski shows off his actual basketball skills. In college, Krasinski coached youth basketball at Gordon School in East Providence, Rhode Island.