With many fantasy drafts having already been conducted, a number of potential impact fantasy players remain as free agents in a majority of leagues. Owners that have some extra space on the bench as the year begins will want to keep these sleepers in mind.

For the second consecutive year, Chris Johnson and Maurice Jones-Drew have been two consensus first-round fantasy selections. Their value is due not simply to their talent but also to the fact that they have very little competition from their teammates to take away playing time.

Even so, surprisingly few fantasy owners have thought to insure their first-round draft choice with a late-round selection of the backup running backs to these stars. Javon Ringer and Rashad Jennings are key insurance policies for Johnson and Jones-Drew, respectively.

Ringer enters his second season in the NFL after a standout career at Michigan State. In 2009, Ringer saw the field only sporadically as Johnson and LenDale White carried nearly all the load for the Titans.

Ringer will not be able to replicate the production of Johnson if the 2,000-yard back suffers a severe injury, yet he would become the unquestioned starter on a team with a strong running game. Every owner that drafted Johnson should strongly consider acquiring Ringer before a competing owner acts sooner.

The same philosophy holds for Jennings, the backup to Jones-Drew in Jacksonville. Jennings was not as much of a star in college, toiling in relative obscurity for the Liberty Flames. The second-year back had 303 total yards in 2009 and reached the end zone once. Similar to the Johnson-Ringer tactic, owners of Jones-Drew ought to contemplate snagging Jennings.

Another running back that enters the season as a fantasy sleeper is Washington running back Ryan Torain. Torain currently sits third on the Redskins' depth chart behind injury-prone veterans Clinton Portis and Larry Johnson.

The 29-year-old Portis played eight games last year, the second time in four seasons he missed half his team's games. Johnson, 30, has not played a full season since 2006 and has averaged a meager 3.8 yards per carry over the last three years.

An ineffective showing from this duo is hardly out of the realm of possibility. Mike Shanahan has a notoriously short leash with his running backs, so Torain may see plenty of action for Washington.

Torain previously played for Shanahan in Denver and started a Thursday night game for the Broncos in November 2008, rushing for 68 yards and a score in the first half before injuring a knee that caused him to miss the rest of the year and all of 2009. Torain's injury record is not much better than that of Portis or Johnson, but his familiarity with Shanahan makes him someone to track.

In San Diego, wide receiver Vincent Jackson is holding out for a larger contract despite a three-game suspension hanging over him. Many fantasy owners expect Malcom Floyd to become the favored target for Philip Rivers in Jackson's absence, although Legedu Naanee could emerge as a top receiver as well. Naanee is available in the vast majority of leagues and is a prime free-agent acquisition if Jackson continues his holdout or is traded.

The current St. Louis Ram offense is a far cry from the juggernaut it was in the early part of last decade. Now directed by rookie quarterback Sam Bradford, the Rams have just one proven fantasy star, running back Steven Jackson. However, Bradford needs a target to whom to throw, and with last year's top receiver Donnie Avery out for the season with an injury, Laurent Robinson becomes the No. 1 wideout.

Robinson had 11 catches for 141 yards and a score in his first two games of 2009, before suffering an injury in Week 3 and being lost for the year. Robinson is unlikely to have enough of a bearing to be a top fantasy receiver, but he has potential to be a low-end No. 2 receiver or a bye-week replacement.

Dan Massey's Fantasy Sports appears each Sunday. E-mail him at dmassey@lnpnews.com.