Fantasy football research never stops, and roles change drastically from one week to the next. That's where our fantasy football mailbag comes into play.

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Now, let's answer some questions.

Email submission from Matthew Gilmete:

Hey, I have a question. Right now I have a surplus at the RB position (Mccoy, Gurley, Gordon, CMike n possibly Dixon). My WR are Marvin Jones, Diggs, Emmanuel Sanders, Enunwa and underachieving Michael Floyd. My TE is Eifert, QBs are Dalton and Wentz. My other league mates are hurting at the RB position, im thinking of selling high on Gordon for a WR, what should I expect in return or what should I go after?

As mentioned yesterday, Melvin Gordon might not be a guy to sell despite his touchdown-dependent output thus far. In this specific situation, though, such a thought is fine as long as you're getting quality return.

The difficult part of Gordon is assessing how we should view him. On the one hand, he's a workhorse running back who is attached to one of the most efficient passers of the past decade in Philip Rivers. Additionally, he's seeing plenty of work in the passing game with a 13.6% target market share over the past three weeks. There's tons of fantasy value in that, and we shouldn't just move him due to a few down weeks in his rushing production. This is why we should be soliciting a second-tier wide receiver in return if somebody wants to pry Gordon away.

It's possible that the more desirable "sell" candidate here is Todd Gurley. Gurley has revived his value a bit by finding the end zone three times in the past three games, and his passing-game involvement has been a solid addition. However, Benny Cunningham is expected to return in Week 6, and he had been the team's passing-down back earlier in the year. Gurley's value could sink again, and that may nudge him ahead of Gordon as the guy to move.

There's tons of ambiguity around Dez Bryant right now, specifically when he's due to return for his injury. Even with that factor in mind, this is probably still a trade you should consider.

Bryant is expected to practice a bit today, according to Jon Machota of the Dallas Morning News, meaning if he's not back this week, he should return following the team's Week 7 bye. With how efficient Dak Prescott has been this season, he'd be returning to some serious touchdown upside, and that's not necessarily a factor working in Terrelle Pryor's favor.

With Pryor, you love that he has 27.1% of the team's targets this year. However, only three of those targets have come in the red zone, and Corey Coleman's eventual return could put a dent in Pryor's market share. Pryor's a fine asset with a respectably high floor going forward, but we do need to temper expectations given the team's struggles and the impending increased competition for looks.

This is something of which we'll have a better idea as the week progresses. Ideally, you'd like to see Jamaal Charles get in full practices throughout the week, in which case you can fire him at will. If he doesn't, then the decision becomes a bit tougher, but he's still at least worthy of consideration.

The Kansas City Chiefs felt comfortable enough with Charles' knee to roll him out in Week 4 with Charcandrick West out, a move they probably wouldn't have done if he were still on the mend given their Week 5 bye. After an additional week of rest, Charles should see an up-tick in snaps, likely including some passing-game usage. That's a beautiful thought against the Oakland Raiders.

Through the first five weeks of the season, the Raiders own numberFire's 29th-ranked pass defense, allowing every opposing quarterback except for Marcus Mariota to pass for at least 298 yards against them (with three players topping 350). This team is getting gashed defensively, and that helps brighten Charles' outlook. As long as we can assure his snap rate will go up a good amount this week, Charles is absolutely worthy of a roster spot given his matchup.

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