At this juncture, two things are becoming very clear: Eric Thames was a bargain in fantasy drafts and Byron Buxton is an albatross on your team. If you bought low on Thames or managed to snag him off the waiver wire, congrats. If you've had the misfortune of watching Buxton rack up Ks in your starting lineup, condolences. While April doesn't make or break a player's season, it's far enough along that we can assess players based on their current rankings.

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.

Early in the season, my values will be based more on ADP than performance due to small sample size. I will include one player at each key position group (Infield, Outfield, Starter, Reliever). Ownership levels are taken from Yahoo! Fantasy Sports.

Underrated Players - Week 4

Taylor Motter (SS/OF, SEA) 16% owned

For a team looking to rebuild with youth, you'd think the Rays wouldn't be so keen to give away power-hitting infield prospects before the season even started. Nick Franklin and Taylor Motter were both ditched by the team and may find themselves with successful careers in new homes. Motter has already gotten started by hitting four home runs with eight RBI in just 43 at-bats. He's slugging an impressive .718, which currently leads the AL. Not bad for a temporary replacement. Motter will slide out of the shortstop spot as soon as Jean Segura returns, but he could find a home at first base or become a part-time player. He may no longer be worth starting in mixed leagues, but he's a definite hold in AL-only leagues and could be worth a bench stash.

Steven Souza Jr. (OF, TB) 49% owned

We know Souza won't hit anywhere close to his current .349 average by season's end, so let's get that out of the way. His .452 BABIP means regression is on its way sooner rather than later. That said, Souza's power will not go away and he could be a 25 HR waiver wire add. He is known to strikeout a ton, but Souza has been disciplined so far with an 0.56 BB/K rate that is far better than last year's 0.19 BB/K. Tampa's offense is exceeding expectations all around, but that doesn't mean there isn't long-term value here. Grab Souza for his power and run producing value as long as you know what you're getting yourself into - a likely .250 hitter with a 25/80 ceiling.

Michael Wacha (SP, STL) 68% owned

The fact Wacha is still available in over one-fourth of fantasy leagues shows that the recency bias is real. Wacha's 5.09 ERA and 1.48 WHIP last year made him at best a deep sleeper in preseason drafts. Those lottery tickets are starting to pay off, as Wacha has a 2.41 ERA and 1.13 WHIP after three starts. If not for three long balls, Wacha would be near flawless so far. It might be concerning that his fly ball rate is up to 46%, but that should settle down closer to his career mark, along with the inflated 1.45 HR/9. The best sign is that his K/BB is up to 3.45, although his command never really abandoned him. Wacha got away from his fastball last year and relied more on his changeup, which proved unsuccessful. That and he had some bad luck last year (.334 BABIP). Wacha won't blow you away in any category, but he's a solid SP4/SP5 in mixed leagues that is worth adding or buying cheap.

Brad Brach (RP, BAL) 61% owned

By now, Brach should be universally owned. If you haven't heard, All-Star closer and Cy Young candidate from 2016, Zach Britton, is on the DL for the foreseeable future. Brach is taking over closing duties and has been lights out so far. He has saves in three straight games to go along with the five holds he'd already accumulated. Brach has yet to allow a run and has registered 12 K in eight innings. He is the rare middle reliever who has earned an All-Star berth himself, so it should come as no surprise that he is comfortable in the ninth inning. Even if you aren't in need of saves, scoop him up and deal from your new position of strength.

Overrated Players - Week 4

Travis Shaw (1B/3B, MIL) 59% owned

He's on fire - pick him up! He's cold... bench him for now. He's on fire again - quick, put him back in! Such is the life of a Travis Shaw owner. After collecting a homer, four doubles and five RBI in the first three games of the season, Shaw was looking like he might be the real sleeper on the Brewers roster. Five hits in 10 games later, he's down to .200 on the season and we've forgotten about him. Another power surge has made him a top waiver pickup once more, but how long will it last? Shaw started like a house of fire last season in Boston too, hitting .314 in April, .275 in May and driving in 35 runs over the first two months. If you were a Shaw owner who didn't sell high at that point, you were sorely disappointed to see him hit .194 with only 23 RBI in 193 at-bats over the second half of the season. Shaw is not only as streaky as they come, he doesn't have the pedigree to support a breakout season. His career high was 16 HR in a minor league career that spanned five seasons. His walk rate has been declining each year, down to a low mark of 7.4% this season and he has an unsustainable 35.7% HR/FB%. Stream him through the spring, but don't hesitate to bench or sell him as soon as the next cold drought comes on.

Odubel Herrera (OF, PHI) 87% owned

Herrera projected to be a top-25 outfielder with a legitimate shot to go 20/20 this season. He hasn't gotten off the kind of start you'd like, hitting .264 with one homer and four RBI, although the two steals are somewhat helpful. Herrera is reaching base at a high clip thanks to an increased walk rate of 14.5%, but he's hitting ground balls at a higher rate (53.8%) and making less hard contact so far (15.4%). In a small sample size, these shouldn't be major concerns yet, but playing time could be. The Phillies have a glut of outfielders that they seem bent on rotating in and out of the lineup. Herrera himself was benched more frequently in early August last season when he was struggling, so he could lose a few at-bats here and there if he does hit a slump. Add in the fact that he isn't seeing much support behind him with Maikel Franco hitting .172 and Herrera isn't living up to his ADP. You can stay the course if you have faith in the Phillies, but I have my doubts about a team that seems uncertain about its direction.

Ervin Santana (SP, MIN) 90% owned

Your top-ranked fantasy pitcher after three weeks is none other than Ervin Santana. His 4.10 SIERA is drastically different than his 0.64 ERA, however, so there is bound to be some hard regression soon. Santana has only posted an ERA over 4.00 over a full season once in the last seven years, so we shouldn't expect a complete implosion. The problem is that he won't help you in enough other categories to warrant holding onto. He's striking out a league average 20% of batters, as he's done his whole career. Don't count on the wins to continue either - he only tallied seven each of the last two seasons with Minnesota. Santana has been around long enough that most seasoned fantasy players won't be fooled by a trade offer of Santana for deGrom, but it won't hurt to dangle him to a desperate MadBum owner to see what you can get in return.

Andrew Triggs (SP/RP, OAK) 49% owned

It's a bit surprising that more people haven't bought into the pitcher with the longest scoreless streak to start the year so far, but perhaps there's a good reason. Triggs has gone 17 2/3 scoreless already, but is only half-owned. The reason is that he doesn't have a track record of Major League success, he isn't doing much in the strikeout category (4.58 K/9), and his 4.18 SIERA suggests that he's not as good as he looks on paper. Triggs is a converted reliever who was thrown into Oakland's rotation because of Sonny Gray's absence. It looks like he will stick now, but there's little chance he keeps this up, at least at this rate. He's got a plus home park factor in his favor and is in a division with teams that are struggling offensively, so you can pick your spots with him, but don't expect him to become a staple in your rotation.