A couple days left for everything to devolve into total chaos and fantasy rosters to be turned upside down. Don't you love the trade deadline? Let's see whose stock is rising and falling this week before it all gets screwed up.

Scouting players who may be undervalued and re-assessing players who may be overvalued is a weekly exercise that you should pursue. Fortunately, I have you covered. Here are a few players who are good buy or sell candidates based on their current performance compared to ownership levels. This could mean scooping them off waivers if possible or actively seeking a trade to acquire or discard certain players in order to maximize value.

I will include one player at each key position group (Infield, Outfield, Pitcher). Ownership levels are taken from Yahoo! Fantasy Sports.

Underrated Players - Week 18

Josh Bell (1B/OF, PIT) 46% owned

Rookies are hard to trust completely, but when you find one that is big-league ready, it can be a game changer. Bell isn't near Aaron Judge or Cody Bellinger territory, but he is slowly working way into becoming a regular starter at the mixed league level. Bell is up to 18 home runs and 55 RBI on the season and is the new cleanup hitter in Pittsburgh. A .249 average may be a bit disappointing, but in the second half so far, he's slashing .308/.345/.519. The return of Starling Marte on top of the lineup should only increase his RBI opportunities. Don't let a slow start deceive you into thinking Bell is just a mediocre waiver wire option.

Josh Reddick (OF, HOU) 54% owned

Reddick had another quietly prolific night at the plate on Friday, driving in five runs. His three-run homer in the eighth inning led the Astros to another victory, giving them double the number of wins (68) versus losses (34) this season. Reddick isn't slugging a ton of homers, nor will he lead the league in hitting, but he's doing un pocito de todo as my Dad would say (a little bit of everything). Reddick is slashing .307/.350/.498 with nine HR, 48 RBI, 58 R, and seven SB. Runs scored are probably the least sexy category in rotisserie leagues, but it counts just as much as the others and Reddick should keep scoring plenty in that lineup. The fact that he's barely half-owned across all leagues can only be a reflection of his injury history, not his performance. Sure, he could get hurt any day now. If that's the case, just drop him and get someone else. Pretty simple actually.

Mike Fiers (SP, HOU) 65% owned

His stock is slowly rising, even if his last start wasn't the prettiest. Fiers has been solid all year for the 'stros, pitching to a 7-5 record, 3.71 ERA, 1.28 WHIP, and 9.2 K/9. He's managed to raise his ground ball rate to a 0.78 GB/FB and his strikeout percentage up to 24% this season. He's giving up too many big flies, but a 14.6% HR/FB could come down eventually if the positive trends continue. Fiers isn't a front-end rotation arm and never has been, but he's thrown enough dominant starts to be worth adding in many mixed leagues.

Overrated Players - Week 18

Eric Thames (1B/OF, MIL) 87% owned

A month into the season I wasn't touching Thames on here with a twenty-foot pole. I had plenty of reservations about his value and whether he could keep up his monstrous home run pace all season. Fast-forward to the end of July and here's what we're looking at. A player with a total of four HR, five RBI in the past month with just one dinger and two RBI since the second half began. Sure, it could just be a slump, but if you take away that ridiculous first month and look at the last three combined, you don't have a special player. He is now hitting .252 and his 45 total RBI don't put him anywhere close to the league leaders. On a per-game basis, backup Jesus Aguilar has actually been more productive than Thames lately. He isn't a drop candidate or anything, but it's finally time we admit that the magic is gone.

Andrew Benintendi (OF, BOS) 88% owned

Bring on the angry tweets... While there is no denying Benintendi is a future superstar and a high-priority keeper in dynasty leagues, he hasn't done much to help fantasy teams this season. His .268 average and .762 OPS are as middle-of-the-road as you can get, while 12 homers and 54 RBI are easily replaceable on the waiver wire. Hell, Matt Adams has given just as much value in 100 fewer at-bats. It may be another year or so before the kid fully develops his talent, but don't expect it to suddenly happen in August or September. Overly high expectations for prospects can be the death knell of many a fantasy team, after all.

Ivan Nova (SP, PIT) 85% owned

Ivan Nova has been as consistent and reliable a pitcher as anyone this year. Correction: Nova had been as consistent and reliable a pitcher as anyone this year, until July hit. He had an uncharacteristic meltdown in his last start, allowing seven earned run against the Rockies. Sure, we could blame Coors Field effect, but it just follows a trend of recent decline. After earning NL Pitcher of the Month in April and continually pitching into the seventh or eight inning, Nova has only gone more than six frames once in his last five starts. He's also given up seven HR in his four July starts, compared to only two in his first six starts of the year. It could be a matter of early fatigue or hitters simply attacking him more aggressively now that they know he is going to live in the zone. Either way, Nova doesn't deliver any strikeout value (5.3 K/9), so without elite-level ratios, he's not going to be of much help.

More Risers and Fallers

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