Whether due to their own play, the play of others, or injuries, players' stock increases and decreases on a weekly basis. Perhaps more than any other, the NFL is a league that experiences ups and downs at a rapid pace. With only 16 games, there’s little room for error and seemingly endless opportunities for improvement. The same goes for fantasy football, and managing rosters effectively is key to winning that championship.

Throughout the season, players get hot and see an increased role while others struggle and fight to stay relevant. Experienced fantasy players know this happens every year. In this weekly column, we’ll showcase those who have taken important steps forward and those who have taken steps back.

These are the key fantasy risers and fallers heading into Week 17 of the NFL season.

• Quarterback fantasy football rankings
• Running back fantasy football rankings
• Wide receiver fantasy football rankings
• Tight end fantasy football rankings
• Kicker fantasy football rankings
• FLEX fantasy football rankings
• Defense (D/ST) fantasy football rankings
• Superflex fantasy football rankings
• IDP fantasy football rankings
• Dynasty fantasy football rankings

Week 17 Risers

Jimmy Garoppolo (QB, SF)

Was it really going to be anyone else? Jimmy Garoppolo is obviously the greatest quarterback in NFL history. He has the highest win percentage in NFL history having won 100% of his games. The biggest question for Garoppolo after his hot start with the 49ers was what will happen when he faces a real defense? After shredding the best defense in the league, I am ready to put him in the real life top 10 and he is certainly going to be one of the first 12 QBs off the board in 2018 drafts. Jimmy G threw for 242 yards and two touchdowns against the Jaguars while adding a third on a QB sneak. He is matchup proof already and he is doing this with Marquise Goodwin and Trent Taylor as his top two weapons. Garoppolo is a must start in Week 17.

JuJu Smith-Schuster (WR, PIT)

What will the Steelers passing offense look like without Antonio Brown? Well, we have our answer and it is in the form of JuJu Smith-Schuster. Over the last two weeks, JSS has caught 12 of 13 targets for 189 yards and a touchdown. He's made plays underneath and over the top. He looks like a complete receiver and he's only 21. It's scary to think how good he could be. With AB out again this week, Smith-Schuster is once again a WR2 with mega upside.

Dion Lewis (RB, NE)

Without Rex Burkhead and James White, the Patriots leaned heavily on Dion Lewis and he delivered. Lewis carried the ball 24 times for 129 yards and scored both on the ground and through the air. Lewis did it all and reminded us of how explosive he can be when given the opportunity. Lewis will remain the feature back in Week 17 with Burkhead still out, Lewis will once again be an elite RB1.

Trey Burton (TE, PHI)

Trey Burton didn't do much of anything in Week 16, but his value is firmly on the rise heading into Week 17. With the Eagles clinched everything and Doug Pederson actually being good at his job, the starters will likely play only a series or two before giving way to the backups. Once Zach Ertz departs, Burton will step right in as an elite TE1 just like he's been every time he's gotten an extended snap share.

Week 17 Fallers

Dak Prescott (QB, DAL)

While I really don't think there's a debate as to who has worse weapons, Dak Prescott or Jimmy Garoppolo (the answer is Prescott), he still isn't performing anywhere near the level he should be. Just one week after watching Jared Goff and the Rams do literally whatever they wanted against Seattle's bottom 10 defensive unit, Prescott couldn't do a thing. He threw for just 182 yards and his only touchdown pass went to the wrong team. It's a lost 2017 for Prescott and with a finished Dez Bryant as his top target, he cannot be used in Week 17.

Alshon Jeffery (WR, PHI)

Alshon Jeffery was probably going to find himself here regardless of how he performed last week as the Eagles are going to be resting starters in week 17, but putting up a goose egg in fantasy championship week is not doing him any favors. After seven consecutive weeks in double digit PPR points, Jeffery didn't catch a pass on Monday night. His zero combined with the limited snaps, if any, that he projects to play this week, make him unplayable for your fake team.

Joe Mixon (RB, CIN)

The Bengals are finishing out a lost season where the lone bright spot was there prized rookie RB. After missing two games with a concussion, Joe Mixon returned in week 16 just to exit again, this time with an ankle injury. There's no way he plays in a meaningless Week 17 game, which is an unfortunate end to a rookie season that should have been better than it was. Mixon is going to be a screaming value in 2018, but it will be the Giovani Bernard show to close out 2017.

Kyle Rudolph (TE, MIN)

I could have gone with Zach Ertz or Evan Engram here, but Kyle Rudolph deserves this spot both for poor play and insufficient play. After catching just one pass last week and mostly being in and out of the lineup with an ankle injury, Rudolph's fantasy value is about as low as it can be. Even though the Vikings can technically still get caught by the Saints next week, they won't push Rudolph more than they have to. Rudolph is not an option for Week 17.

More Week 17 Lineup Prep