This week, it's an unintentionally Rockies-centric piece that will tell you how to handle players that ironically have had nothing to do with the team's success (or recent struggles) this year. Read further to find out more.

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.

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Underrated Players - Week 14

Marwin Gonzalez (1B/2B/3B/SS/OF, HOU) 79% owned

I resisted Marwin Mania in May as best I could. In fact, I did pick him up in one league, only to drop him a couple weeks later. Big mistake. Huge. Gonzalez has seen his ownership decline a bit lately since he's missed time with an oblique injury. That shouldn't mask his tremendous performance this season that has seen no end (yet). Gonzalez is slashing .314/.398/.574 with 13 home runs and 42 runs batted in. He won't pass last year's career high of 141 games played, but he'll still be in the lineup around five times a week, assuming good health. Is there regression to come? Sure. His 23.6% HR/FB is double his career rate and his .343 BABIP is on the high end, but he isn't completely outplaying the level of his abilities. What Gonzalez is doing better is being more patient, with an 11% walk rate that is more than double his usual amount, and hitting more fly balls (more of which happen to be leaving the yard). His pull rate is actually down quite a bit, so if he decides to start sacrificing his all-fields approach (and his average), then he could possibly approach the 30-HR plateau. All that aside, don't tell me there's not a place in your lineup for someone who literally plays every position except catcher in fantasy. If a leaguemate has let him go, grab him now. Otherwise, consider trying to secure him as part of a package deal somehow since he's still considered a utility player.

Hunter Renfroe (OF, SD) 26% owned

If you like sluggers, you should love Renfroe. He is tied with teammate Wil Myers for the club lead in home runs with 16 after jacking another on Thursday. While Myers is universally owned, Renfroe is available is three-fourths of Yahoo leagues, yet has an equal numbers of homers and only three fewer RBI. Sure, he's only batting .225, but Myers is at .262 so there's not a huge leap here. I'm not saying Renfore is equal to Myers in terms of value. I am saying that Renfroe is being overlooked because he's a rookie and his current low average/high strikeout rate makes him seem like another Chris Carter. In truth, Renfroe is a much more disciplined hitter that has yet to adjust his approach. He hit .333 and .307 with K-rates barely over 20% in the last two minor league seasons. He tattoed pitchers to the tune of .371 in an 11-game audition last season, which earned him the everyday right field job this season. Renfroe may not figure it all out in his rookie campaign, but he certainly has the pedigree. Hey, if you would have told me that Aaron Judge was hitting .331 by the All-Star break, I'd have said you were crazy. I can only imagine Renfroe in that Yankees lineup instead...

Jon Gray (SP, COL) 46% owned

He's back! As someone who was banging the drum for Gray all last season, I have been eagerly awaiting his return. Gray was set to build on an impressive rookie season marred by just a couple of bad outings when he suffered a stress fracture in his left foot. He showed no signs of trouble in recovery and then promptly picked up a win against the D-backs on Friday, allowing just two runs over six innings with 10 K. Gray started the trend last year of rookie starters in Colorado being fantasy viable and the mantle has been taken up by several players like Antonio Senzatela, Kyle Freeland, German Marquez, and Jeff Hoffman. Last season, Gray struck out nearly 10 batters per nine innings and pitched to a 3.72 SIERA. Keep in mind, this is for a player that was available for free on the waiver wire. Now that the Rockies have become a winning team and Gray has a year under his belt, expect better things. He's an easy add in mixed leagues everywhere.

Overrated Players - Week 14

Troy Tulowitzki (SS, TOR) 67% owned

Can we please stop pretending Tulo plays in Colorado? Since joining the Blue Jays, he hit .239 in the second half of 2015, .254 in 2016, and is at .233 so far this season. He did show some pop last year with 24 HR, but he's only gone deep four times in 44 games in 2017. He's hitting the ball on the ground in half his at-bats and making a career-high 25.2% soft contact. Injuries have no doubt contributed to his decline, but that has to be factored into his value because he's proven to be injury-prone throughout his career. Counting on him to be a starting SS is a mistake. To take it a step further, he's more of a liability in your lineup than an asset and you wouldn't be blamed for dropping him.

David Dahl (OF, COL) 41% owned

I've said before that I try not to put injured players on this list, but I'll make an exception in this case. If you aren't in a keeper league, you have no business keeping Dahl on your roster. Dahl was just moved to the 60-day disabled list after suffering another setback in his rehab from a stress reaction in his rib area. While he's been out all year and the move is retroactive, which leaves open the possibility he can still return, that doesn't mean it will happen. The other issue, which never truly went away, is playing time. Charlie Blackmon isn't going anywhere with the team contending. Carlos Gonzalez, for all his struggles, isn't getting moved either with his trade value at an all-time low. Recent signee Ian Desmond occupies the other outfield spot and rookie Raimel Tapia is hitting .299 with 16 runs scored in 28 games. Hypothetically, even if Dahl makes an appearance in August, how much value are you going to extract from him? Don't hold on here unless you've got him at a super-cheap price for 2018.

Gerrit Cole (SP, PIT) 95% owned

I'm actually disappointed that this article is being published hours after Cole's latest implosion because I had him on this list days earlier and now I can't say "I told you so!" Cole had started looking sharper lately, with a 1.35 ERA in his previous three starts. Then, Friday happened. Cole was rocked for seven runs and 10 hits in 5 1/3 innings against the struggling Giants. His season ERA now sits at 4.51 and his record dropped to 6-7. Even at his best, Cole's upside is limited. He averages a modest 8.22 K/9 and is giving up homers at a prolific rate; he saw the 17th ball leave the yard tonight. Yes, I realize that's the same as Clayton Kershaw, but let's not pretend to compare these two. Cole isn't outright droppable, but hoping for a return to 2015 form would be a mistake. That season is looking more like an outlier by the day.

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