Each week of the NFL season, we sift through the deeper options at each position with an eye toward identifying streaming fantasy commodities with valuable matchups to consider.Now that we’ve reached the championship round (for those weeks with Week 17 in play), your main reasons for needing a pickup are often due to injury. Sometimes, though, it’s also because you’re unhappy with the production you’re getting at a certain position and you simply don’t have a better option on your roster. In deeper leagues, those in which you start four or five receivers or employ a wide spectrum of flex spots, you may just need the best warm body available with upside. And no matter your league size, it should go without saying that we strongly advise streaming at defense/special teams (D/ST) and with individual defensive players (IDP) throughout the season.That’s what we’re here for, to identify widely available options that could provide the relief you are seeking this week.Running backNeed an impact player whom others might be overlooking? Here are the top options available on waiver wires in most ESPN fantasy leagues.Wayne Gallman, New York Giants: The final weeks of the NFL season always produce handful of surging running backs who come out of nowhere to accumulate meaningful numbers. Gallman is part of this tailback tradition. Only Le’Veon Bell has more targets at the position since Week 14, while the two are tied with 19 receptions to lead the pack over the past three weeks. The Clemson product has 16.3 touches per game over the past three weeks and a meeting with a Washington Redskins defense that has allowed 25.1 fantasy points per game to backfields over the past five weeks.Peyton Barber, Tampa Bay Buccaneers: The selling point for Barber is purely opportunity driven. Barber’s 17.75 touches per game since Week 13 ranks 21st in weekly workload. The New Orleans Saints are missing their best interior linebacker for the finale, supporting some upside for Barber on early downs.Wide receiverTyrell Williams, Los Angeles Chargers: Air yards help reveal the depth and value of targets. Williams leads the Chargers with 16.5 air yards per target since Week 13, a rate that ranks seventh highest in the NFL over this sample. The Oakland Raiders are near the bottom of the league in several key secondary metrics on Football Outsiders, so Williams could deliver some rewarding big plays given what is such a valuable vertical role.Mike Wallace, Baltimore Ravens: For a streaming option in standard leagues, we find Wallace coming on strong after a slow start to the season. Wallace has at least one 20-yard reception in six games this season and is found at 24th in fantasy points per game among wideouts since Week 11.Tight endAntonio Gates, Los Angeles Chargers: Targeted on a robust 22.9 percent of his routes this past Sunday (Keenan Allen was targeted on 22.5 percent of his routes, for some context), Gates proved he still has real utility as a streaming option in the twilight of his career. The Raiders, meanwhile, have allowed 66.1 yards per game to tight ends, the most in the NFL this season.Benjamin Watson, Baltimore Ravens: Speaking of playing well into the twilight of a career, Watson has nine catches over the past two weeks and is benefiting from Joe Flacco thriving between the numbers over the past month. The Cincinnati Bengals have allowed 55.2 yards per game to tight ends this year, 10th most in the league. It’s a good week to go old at tight end.Defense/special teamsWashington Redskins: The Giants have turned the ball over on 13.1 percent of drives since Week 10, the 12th-highest rate in the league. New York has scored just 1.1 points per drive since Week 10, last in the league. With Washington’s capable pass rushers and outside cover corners, this could be a fun fantasy finish for this quietly strong D/ST commodity.Dallas Cowboys: In deeper leagues with dramatically thin waiver wires, the Cowboys are an intriguing defense to consider this weekend. The Philadelphia Eagles could rest their key skill weapons, while Dallas has allowed no more than 17 points in any game over the past month.Individual defensive playersZach Vigil, LB, Washington Redskins: Nick Vigil was a solid fantasy option for much of the season as a tackle machine in Cincinnati, and now his brother Zach is thriving as a spot starter for Washington. The Redskins’ interior ‘backer delivered the top fantasy score among linebackers in Week 16 and can be added in nearly every ESPN league for this final week of the season. Another key linebacker in free agency is James Burgess Jr. of the Cleveland Browns, as he’s tallied at least seven tackles in three straight and is deployed aggressively in blitz packages.Chris Conte, DB, Tampa Bay Buccaneers: Back in the mix in Tampa’s secondary, Conte has 16 tackles over the past two weeks and could be busy chasing down the Saints’ gifted backfield this Sunday.Preston Smith, DL, Washington Redskins: Ryan Kerrigan gets the hype as the edge menace for Washington, but Smith has been quietly stellar this season and has three sacks over his past two games. Another rising name on the line is the Detroit Lions’ Ezekiel Ansah, who is still floating in free agency in well over 90 percent of leagues given some inconstant results this season. With four sacks in the past three weeks, it’s time to trust Ansah as a big-play option again.