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 13 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 13 Risers

Jimmy Garoppolo (QB, SF)

Jimmy Garoppolo literally threw two passes last week, yet his arrow is pointing as high as it ever has. After C.J. Beathard suffered a knee injury on the 49ers final drive in garbage time, Garoppolo was forced into his first action as a 49er. He threw two passes, one for a touchdown. It seems unlikely that the 49ers acquired Garoppolo just to have him watch Beathard from the sidelines. It just doesn't make sense. With Beathard banged up and Garoppolo looking the part, albeit in a very, very small sample size, it seems incredibly likely that Kyle Shanahan will name Garoppolo the starter for the rest of the season. With the Bears crumbling defense up next followed by the Texans laughably bad pass defense, Garoppolo is a legitimate streaming options for those in need.

Julio Jones (WR, ATL)

I could've gone with Keenan Allen or Cooper Kupp, but let's go with the big name who finally gave us a big performance. Julio Jones put up a whopping 50 fantasy points last week as he amassed 24% of his season yardage total in that game alone. Jones had been consistently good all year, but we don't draft just good in the first round. Last week, Jones was, to steal a line from Ray Hudson, "magisterial." Hopefully, this is the start of a scorching finish for the elite WR1.

Joe Mixon (RB, CIN)

This man deserves this spot. Joe Mixon is the unholy offspring of Le'Veon Bell and Ezekiel Elliott. He runs between the tackles with power. He has patience behind the line (which isn't very good to begin with). He can switch directions at will. And he can make defenders miss. Mixon has it all. He is a future elite RB1 once the Bengals fix their offense. He flashed all of that ability last week, setting career highs in carries, rushing yards, and total yards. Mixon's touch floor has been amongst the highest in the league since Jeremy Hill went on IR (also Jeremy Hill should not be on the Bengals next year, or an NFL roster for that matter) and now he's shown his ceiling. If you stuck by Mixon and made it to the playoffs, he's the type of guy that can propel you to a championship.

Ricky Seals-Jones (TE, ARI)

This one is fun! This is probably just a flash in the pan because Ricky Seals-Jones is not particularly talented and is on a weaker offense, but when a rookie TE comes out of nowhere and scores three touchdowns in two weeks, he deserves a spot on the risers list. The man who will henceforth be known as RSJ posted a 4-72-1 line last week against the best defense in the NFL. Good for him! This is a great story that probably won't have a cinderella ending, but at least years down the line, I can say I once wrote a blurb about Ricky Seals-Jones.

Week 13 Fallers

Dak Prescott (QB, DAL)

It is really hard to end up on the fallers list two weeks in a row. That implies that after falling, you fell some more. Somehow, Dak Prescott accomplished this feat of incompetence. Through the first nine weeks, Prescott was a QB1 in eight of them and the only time he wasn't was because he played well, but Ezekiel Elliott stole all of the touchdowns. Zeke hasn't been around to steal touchdowns. That's mostly because Elliott literally isn't around, but also because there are no touchdowns to steal. Prescott hasn't thrown for a touchdown since November 5 and last week's 179 passing yardage total was actually his highest in his last three games. I can't remember the last time an elite QB1 fell this far this quickly. At this point, there is no justification for starting Prescott until he shows us something.

Doug Baldwin (WR, SEA)

Back to back weeks for this guy as well. Last week, he was here and I cautioned that he might not be an every week starter anymore. Now, I really don't know how he can be started in fantasy leagues. He's almost at the point where he's droppable. For reasons unknown, Doug Baldwin is being phased out of the offense. The Seahawks are scoring points, but Baldwin is nowhere to be seen. It's not like he's suddenly bad at football, which makes this all the more difficult. Baldwin is still talented, he's irrelevant. The Seahawks have scored 22, 34, and 24 points in each of their last three games. Over those three full games, Baldwin has a total of 15 targets. Yes. 15. Across three games. Between the 20s, Russell Wilson looks for Paul Richardson and Tyler Lockett. In the red zone, he's looking at Jimmy Graham. Baldwin has a total of four receptions over his last two games and his rest of season schedule is not very favorable.

Kareem Hunt (RB, KC)

Yep. We're doing a trifecta of repeats because all three of this guys deserve the bashing. Kareem Hunt was way overvalued early in the season. That was obvious. While a regression was expected, this is overkill. Hunt managed a paltry 17 yards on 11 rushing attempts and somehow finished with fewer fantasy points than part-time backfield mate Charcandrick West. With Andy Reid completing mismanaging his offense and allowing teams to easily contain Hunt, even with the favorable rest of season schedule, it's hard to bank on a turnaround. Hunt is certainly talented to do it and I doubt you can afford to bench him, but, like Baldwin, we're at a wait and see point for the rookie.

Greg Olsen (TE, CAR)

It is always tricky returning from foot injuries and Greg Olsen was no exception. After rehabbing and finally getting back on the field, Olsen aggravated his previously broken foot after catching just one pass and did not return. He thinks he's fine. I disagree. Even if he does play this week, his risk for reinjury is high and he's a very dangerous start in fantasy leagues as the prospect of him exiting early with minimal production is very real.

More Week 13 Lineup Prep