BOULDER — Demetrius Sumler can't pinpoint when it occurred, but at some point during the past 10 days, many of the finer points in becoming a Division I-A running back converged for him.

Result: Despite what's shown at tailback on the University of Colorado depth chart, Sumler, a redshirt freshman from San Diego, is neck and neck with Hugh Charles, the incumbent starter.

"He's just giving us a lot more — his speed hitting the hole, his vision, his balance; he's done everything right (in camp)," running backs coach Darian Hagan said of Sumler. "It's just hard to keep him off the field."

A strong showing in last weekend's scrimmage shoved Sumler past senior Byron Ellis and into position to share practice repetitions with Charles in the No. 1 offense. CU's first camp depth chart, released Sunday, shows Sumler behind Charles, Ellis and sophomore Kevin Moyd.

Hagan contends the tailbacks were listed alphabetically, although none of the other offensive groupings were constructed that way. No matter; Sumler, who finished his high school career as the San Diego area's career rushing leader, ignored the listing.

"To be honest, (Hagan) didn't even talk about it and we didn't discuss it with him," Sumler said. "I know I've progressed, but I don't want to relax."

Hagan said he won't hesitate to substitute Sumler for Charles "in whatever we script. If it's a play he does consistently well, and it's the first play coach (Mark) Helfrich (offensive coordinator) calls, he'll be in there."

ETC.: Coach Dan Hawkins said offensive captain Bernard Jackson's status is "doubtful" for the Sept. 1 opener against . Colorado State. Academic issues have curtailed Jackson's practice time. Hawkins said Jackson took one final exam Wednesday with another scheduled "in a couple of days. He's got some extenuating circumstances that would be tough on me. My heart goes out to the guy; he's got a lot of irons in the fire." . . . Today's final camp scrimmage features situational work and is closed to the public.

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