Justin Jackson among top fantasy football free-agent finds for Week 15

Mike Clay's Week 14 biggest takeaway: Sit all Ravens RBs (1:02)

Mike Clay lists his fantasy takeaways for Week 14, including sitting Derrick Henry and all Ravens running backs. (1:02)

Last week's column began by reminding you that during the playoff stretch (and we're in the thick of it), the reality is you probably aren't making significant changes in your lineup. The stars of your squad carried you to the postseason and will likely determine your championship status during the next three weeks.

But things change and happen; last week James Conner and Matt Breida were ruled out for their respective teams by Tuesday morning, causing Jaylen Samuels and Jeff Wilson Jr. to rise out of obscurity to become the two most popular waiver adds.

The waiver wire can be an outlet to plug holes on your roster, like those instances above, but can also be a place to prevent your opponent from plugging a hole on her or his respective roster. We call it defense. Waiver-wire defense.

Let's say, for example, your Week 15 opponent has been starting Jameis Winston at quarterback of late but is wary of a matchup against Baltimore on the road (given that the Ravens have allowed fewer than 200 passing yards per game at home this season and a total of seven passing touchdowns in six contests).

Your opponent might consider a streaming option to fill the gap for Winston and try to advance to the finals. Conversely, your roster is set. You know the players you want to play and have hardly a consideration to make in regard to potentially benching someone. If there's a particularly desirable quarterback option available in the league that you sense your opponent might try to add, go ahead and throw a claim in. This isn't tomfoolery or out of bounds ... it's strategy.

So look around your league, scan the roster of your opponent and size up whether a move -- even one that won't affect your lineup -- might make sense.

Players must be available in over 50 percent of leagues on ESPN.com to be eligible for this column.

Justin Jackson, RB, Los Angeles Chargers (43.2 percent): It's no guarantee that either Melvin Gordon (knee) or Austin Ekeler (shoulder) will be available for the Chargers this Thursday night against the Chiefs. Should one or both of them sit out, Jackson will be in line for a massive workload after handling seven carries in Week 14. The seventh-round rookie out of Northwestern has shown promise this season and would face a Chiefs defense among the worst at defending running backs in fantasy football this season.

Elijah McGuire, RB, New York Jets (11.7 percent): Starter Isaiah Crowell left the Jets' win against the Bills because of a toe injury that had him murky to play going into it. McGuire stepped in as the de facto starter, seeing 17 carries for 60 yards and a touchdown. Although it's difficult to trust anyone on this Jets offense because of an inefficient season overall, McGuire would step into flex territory if Crowell does not suit up in Week 15.

Chris Ivory (5.0 percent) and Marcus Murphy, RB, Buffalo Bills (.3 percent): With LeSean McCoy leaving the Bills' Week 14 loss early because of a hamstring issue, Ivory took over as the workhorse temporarily. He too left the game with a shoulder injury. It's too soon to know for sure whether Ivory will be available in Week 15 (same goes for McCoy), but in the event that McCoy misses, Ivory is the preferred Bills back if he plays. That being said, if Ivory and McCoy are out, Murphy is a player who should be added. He would likely be in line for a significant workload.

Damien Williams, RB, Kansas City Chiefs (14.0 percent): Spencer Ware was banged up during Week 14, and Williams -- who played one more snap than Ware -- scored two touchdowns. If Ware is unable to play on a short week this Thursday, Williams would vault up into a top-20 play at running back.

DaeSean Hamilton, WR, Denver Broncos (5.5 percent): Following an injury to Emmanuel Sanders, the Broncos immediately needed passing-game reinforcements. Hamilton, a rookie out of Penn State, answered the bell with seven catches and a touchdown on 69 snaps, most among Broncos wideouts. It's going to take a collective effort to fill the Sanders void, but Hamilton did enough in one week to merit consideration in fantasy leagues. Kudos to my best pal Matthew Berry for suggesting Hamilton as his Week 14 long shot on Fantasy Football Now.

Dante Pettis, WR, San Francisco 49ers (19.6 percent): It's fun to watch Pettis, an electric second-round rookie who has a touchdown in three straight games (four in total during that stretch). The 49ers will continue to lean heavily on Pettis and Marquise Goodwin down the stretch, and while Pettis' volume is not dominant, he's an explosive player who can slide into a deeper-league flex spot for a manager chasing upside.

Ian Thomas, TE, Carolina Panthers (25.5 percent): With Greg Olsen on injured reserve, the Panthers were in need of a tight end to step up, which Thomas did. He hauled in nine catches on 11 targets for 77 yards in a defeat against Cleveland. This much we know: When Olsen is out, Thomas is the guy in Carolina. He's had at least five targets in four games this season, all of which occurred either when Olsen was out or when he was injured early in the game. He's a starting option going forward.

Theo Riddick, RB, Detroit Lions (36.9 percent): Riddick is one of those players who feels bound to remain on this list for the duration of the season, as he isn't a must-start by any means but has enough value in a deeper PPR format because of his pass-catching acumen to stay on the radar. With 32 catches during his past six games, Riddick still feels like the steadiest play in the Lions' backfield until Kerryon Johnson returns.

Tim Patrick, WR, Denver Broncos (.6 percent): That's right, two Broncos wide receivers make this column, as Patrick actually led the team with 10 targets and seven catches of his own. Patrick is a massive target at 6-foot-5 and a player whose development has been noted and appreciated in Denver. While I feel as though Hamilton has more natural ability and upside in fantasy football, Patrick is another deep-league consideration. And kudos to the great Chris Mortensen for making Patrick his Week 14 long shot on Fantasy Football Now.

Curtis Samuel, WR, Carolina Panthers (32.5 percent): During the past two games, Samuel has seen his target share rise steadily for the Panthers, hauling in 10 catches on 19 targets. Given that Samuel had just 25 targets all season prior to these two games, its safe to say the Panthers have made an effort to get him more involved. While he's not yet a starter in lineups, it's not unreasonable to say he's the second-most-interesting Panthers receiver behind DJ Moore -- ahead of Devin Funchess.

Josh Allen, QB, Buffalo Bills (16.9 percent): How risky do you feel? That's what it would come down to if you want to start QB Josh Allen, who has been on an absolute tear with his legs during the past three weeks. Allen rushed for 335 yards, helping him to at least 19 fantasy points in each outing. He's completed just 50 percent of his passes during that stretch, so it's clear the value in Allen is tied to his rushing. Can it persist? He's averaging 10.3 carries during the past three games ... so for now, I still view him as a better option in a two-quarterback league.

Vernon Davis, TE, Washington Redskins (5.0 percent): Jordan Reed left the Redskins' disaster against the Giants with a foot injury, putting him in jeopardy of missing his first game this season in Week 15. Davis would be the next man up, and we know he is a capable pass-catcher and still a very good athlete. The Redskins' offense is a disaster right now, but Davis is an add at tight end due to the lack of depth at the position.