Number 31 was nowhere to be found on the field at McDaniel College as the Baltimore Ravens opened their training camp on Friday morning.

But running back Jamal Lewis, the NFL's reigning offensive player of the year, really was there as the Ravens practiced in helmets and shorts. He was just wearing a blank purple jersey instead of his usual No. 31.

A practice without Lewis -- who rushed for the second-highest total (2,066 yards) in league history last season -- is not something the run-oriented Ravens are eager to see. But it is something that could happen at some point this fall.

Lewis was indicted on federal drug conspiracy charges in February; he and a friend were charged with conspiring to possess, with the intent to distribute, five kilograms of cocaine and using a cell phone in the commission of that act.

A trial date has yet to be set, though it appears as if the trial could be held during the season. Lewis's lawyer, Donald Samuel, has said that a request will be made to postpone the trial until after the season.

Lewis has said that he thinks it would be possible for him to go from the trial to a game, similar to what Kobe Bryant did during this past season with the Los Angeles Lakers. But Coach Brian Billick expressed doubts about such a schedule.

"It's hard for me to imagine that a player, given those circumstances and the amount of time and attention that would require, could emotionally, mentally, even physically, be ready to take on the rigors of an NFL game on Sunday," Billick said Thursday. "But I won't totally dismiss it."

There is no question that Lewis is the centerpiece of the Ravens' offense; he accounted for nearly half of Baltimore's total offense in 2003 (2,271 of 4,929 total yards). He had 387 of the Ravens' 553 regular season carries.

But if Lewis isn't around, the Ravens will turn to two young running backs, Musa Smith and Chester Taylor.

A year ago, Smith and Taylor combined for 307 yards on 72 carries; those numbers should increase. The Ravens want to keep Lewis under 400 carries -- and they would prefer for him to have fewer carries than he did last year -- which means more of a role for Smith and Taylor.

The Ravens felt comfortable enough with Smith and Taylor that they did not seriously pursue or draft any running backs.

"We think they're both rising stars," running backs coach Matt Simon said during minicamp this spring. "Chester has exceptional vision skills, and his lateral quickness is rather extraordinary. Musa has excellent explosive power, slasher-type speed. Those are qualities that are really rare in our business. I think they're great complements to Jamal."

Simon envisions Taylor as having a role similar to that of Priest Holmes's during the 2000 Super Bowl season; that year, Holmes ran for 588 yards (second on the team behind Lewis) and caught 32 passes for 221 yards.

The Ravens selected Smith in the third round of the 2003 draft after he ran for 1,324 yards during his junior year at Georgia. Smith got plenty of work at running back during minicamps, and he will get some more during the next month. He said he feels much more comfortable in his role this year; even the time on the sidelines helped him, as he learned by watching and asking questions. "Knowing the offense, it makes your job 10 times easier," Smith said.

Smith is well aware of the uncertainty surrounding Lewis's legal situation, and he plans to be ready.

"A lot of people bring up that situation," Smith said. "Jamal, the amount of carries he takes, anything could happen. Like they say, you're one play away. I've just got to be ready, no matter what."