The search for start-worthy running backs never stops in Fantasy Football.

A few running backs you drafted and pegged as starters won't be available for Week 1. Obviously that includes suspended Steeler Le'Veon Bell, but now it looks like Jamaal Charles could remain sidelined as he puts the final touches on his rehab from a torn ACL. Other teams such as Baltimore and Seattle have question marks at running back heading into the first weekend.

So how much is too much to "rent" a starting running back for the early portion of the season?

DeAngelo Williams PIT • RB • 34 2016 preseason stats ATT 4 YDS 12 TD 0 TAR 4 REC 3 REC YDS 9 REC TD 0 View Profile

Spencer Ware KC • RB • 39 2016 preseason stats ATT 24 YDS 85 TD 3 TAR 8 REC 8 REC YDS 50 REC TD 0 View Profile

We know Williams will get extensive opportunities for the first three weeks while Bell sits out. He's the most attractive running back to target for an early-season boost, but you have no chance of getting him if he's on the same roster as Bell. You also have no chance of getting him if the Williams owner doesn't have another running back to replace him. But Williams himself doesn't have much long-term appeal because he won't be a reliable starter in Fantasy once Bell comes back. His value will sink. So, anyone trying to trade Williams away shouldn't expect big value.

Eli Manning, Chris Ivory, LeGarrette Blount, DeSean Jackson or Travis Kelce should be fair enough exchanges for Williams.

Ware's not exactly in the same situation. His status is tied to Charles' ability to not only get on the field but stay on it for 70 percent of the snaps per week. That might last into October, it might last one or two games. But he should fetch the same kind of player in trade as Williams in non-PPR leagues because he'll likely have at least a minor role once Charles comes back. And unlike Bell in Pittsburgh, Charles is a candidate to re-injure himself since he's coming back from an injury. If that were to happen and Charles would miss time, Ware would emerge as at least a top-20 Fantasy running back.

Blake Bortles, Philip Rivers, Ameer Abdullah and Emmanuel Sanders are additional players you could get for Ware in PPR formats.

What are the Trade Values? The chart is designed to help guide you in making fair trades in your standard-scoring or PPR leagues. The values assigned to the players below are a long-term measurement of their Fantasy value. By adding two players' values you could determine what one player you should be able to get in return. This list also works as a "Rest of Season" rankings. Also, any player not on the chart should be considered valued at no more than four points.

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