Justin Upton is threatening to head for junior college this month instead of signing with the Arizona Diamondbacks. Upton is apparently looking for nearly $1 million more than what the Diamondbacks have offered. No overall No. 1 pick has gone unsigned since Tim Belcher in 1983 (by Minnesota). But the buzz around baseball over the last few days is that Upton has made plans to enroll in Louisburg (N.C.) Junior College in two weeks if he and the Diamondbacks can't negotiate a deal. Unlike draft picks who go to four-year colleges, Upton would not totally close the door on signing with Arizona by starting school. Because he's attending junior college, the Diamondbacks would retain his rights until just before next June's draft. But Arizona scouting director Mike Rizzo said the team still regards the start of classes on Aug. 30 as "a deadline to be taken seriously -- because once he goes to school, we'll only have a one-week window [after the 2006 junior-college season] before the '06 draft to get something done. "He's already wasted a half-year of development time. So at least if he signs [this month], he'd be looking at getting some time this fall in the Instructional League or the Arizona Fall League. But if it gets prolonged out, then we've lost that window, too. So from a developmental timetable, this definitely concerns us."