sophomore slump (sof'-more slump) noun. The period of time during a basketball player's second season in which there is a notable decline in productivity as compared to their rookie season, whether due to injury, fatigue, or the inability to cope with the higher expectations placed upon them.

Usage example: Emeka Okafor is suffering through a sophomore slump; his numbers are down and he's been injured most of the season.

Word Trivia:
Emeka Okafor is the most prominent current example of a player going through a sophomore slump. His scoring, rebounding, and shooting are all down from his rookie season (despite a strenuous off-season training program), and he's only played in 26 games due to a litany of injuries. Last year, it was Carmelo Anthony suffering from the dreaded slump, and only a strong finish kept him from sinking into a statistical sinkhole (perhaps it was the coaching change, because he's played much better under George Karl). Carmelo's slump effectively killed my fantasy basketball team last season. And, ironically, Okafor's slump is killing my fantasy team this season. New fantasy rule: No more drafting sophomores.