This must be the week when the action really starts. After a few minor deals here and there in April, I've seen a flurry of activity in many fantasy leagues and have made a couple of major transactions myself. We already have trade advice and strategy readily available, so I'll instead continue to focus on players to target in the open market.

Scouting players who may be undervalued and re-assessing players who may be overvalued is a weekly exercise that you should constantly pursue as a dedicated fantasy baseball manager. 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 typically include at least one player at each key position group (infield, outfield, pitcher) and will never advocate that you buy or sell a player if I wouldn't follow the same advice myself. Now, on to the bargaining table...

Underrated Players - Week 7

Alen Hanson (2B/OF, SF) 15% owned

Desperate for speed? Aren't we all these days... Hanson has a 60-grade speed tool and swiped two bags immediately upon being called up to replace Joe Panik at second base. That's not the end of the story, however. He is a former top-100 prospect that can hit for average and has a little pop too, as evidenced by his three homers, tying him with the aforementioned Panik for the lead among Giants second basemen. Hey, it's something. Hanson has bounced from the Pirates to the White Sox and settled into the role of utility man, but he is just 25 years old and now has another opportunity to morph into the rare and wondrous "post-hype breakout." There are other utility types that are producing just as well, but have far more limited ceilings, such as Daniel Descalso or Kike Hernandez. Hanson might be the boost you need and has upside worth chasing for free on the waiver wire.

Tim Anderson (SS, CHW) 67% owned

That's right, he's in the proper section here. As hot as he's been to start the season, Anderson is getting no love from fantasy pundits who simply look at last year's .276 OBP and 27% K% and move on. Anderson is legitimately improving his plate discipline and stealing second base every chance he gets. In fact, he's just five walks away from matching his career high for an MLB season (13) and has already matched his SB total from 2016. In one sense, that shows just how bad his walk rate was in his first two seasons, but progress is progress. As a former first-round pick and one-time top 20 prospect according to BP, it's hard to understand why some fantasy owners are still so skeptical. There's no reason to think he won't finish 20/20 or better this year and his .286 BABIP could indicate some positive regression to come. The shortstop position has been deeper than expected this year, but Anderson could hover around the top 10 if he keeps up his current pace.

Luis Castillo (SP, CIN) 69% owned

If you've been following the Cincinnati Reds every five days and watching film clips of arm angle adjustments, you might be a Luis Castillo owner. There isn't any other compelling reason to follow the Reds this season, but Castillo has been an intriguing case. More than a simple case of sophomore slump, Castillo's early problems have been attributed to a slight change in his throwing motion. This has been fixed, according to the team's pitching coach, and it's hard to argue with recent results. Castillo was one out away from tossing a second consecutive quality start and he struck out seven batters in each game. The now punchless Dodgers await on Sunday and a third straight solid outing could shut the buy-low window completely. Make an offer to the Castillo owner in your league as soon as possible.

Luke Weaver (SP, STL) 75% owned

It's been a bad stretch for the second-year starter, who is slumping even worse than Castillo. He started out on fire, allowing a total of four earned runs and walking five batters in his first three starts. Since then, he's given up at least four runs in each of his last four starts, including a six-walk game against the Mets. His 2.13 K/BB is now half of last year's ratio. Was last year a flash in the pan? It doesn't seem so. He's not getting beat up by opposing batters, with a BAA that's identical to last year's .252 and a hard-hit rate that's barely higher than his rookie year. He's had some bad innings that have cost him in the runs department, by putting runners on base and not being able to strand them. Much like Castillo above, it's part of the learning process that should resolve itself soon. Weaver is a talented pitcher and it's not as if these struggles have been going on since Opening Day.

I've seen Weaver put on the trade block in half my leagues and I have acquired him twice in the past week. Once, it came in a multi-player deal too complicated to mention here and the other was straight up for Jed Lowrie. I plucked Lowrie off waivers about two weeks ago, while Weaver was nearly a top-100 selection in many leagues (105 ADP in NFBC leagues). If you can manage a deal similar to that, now's the time. As always, remember that you want to pay for future performance, not past. Weaver has a choice matchup against the Padres on Friday night that could be the key to a turnaround or drive his value down even further.

Overrated Players - Week 7

Didi Gregorius (SS, NYY) 94% owned

OK, it's over, back to your seats people. The Didi show was spectacular while it lasted, but it's clearly over. After hitting seven homers and knocking in 17 runs in an 11-game span, regression has slapped him and his owners in the face. This week has been particularly hard, as he is hitless in his last 23 plate appearances. He hasn't homered in two weeks and hasn't been crossing the plate either, which just four runs. He'll be fine the rest of the season, but if someone is willing to pay for his inflated May stat line with a premium player that you could use, it's worth dangling his name in trade talks to see what you can get in return.

Jonathan Villar (2B/OF, MIL) 54% owned

Villar got our hopes up with a relatively good start to the year and he's chalked up six steals in just over a month. The problem is he's got nothing more positive going for him. If you're hanging your hat on a .270 average and semi-regular playing time, you probably are desperate for a middle infielder with some semblance of speed and talked yourself into adding him. His plate discipline is even worse than last year (0.18 vs 0.23 BB/K), with half the walk rate of his breakout 2016 campaign. His .394 BABIP is due to decline and he has just one home run. The steals are nice, but you could just pickup Jose Peraza or Jace Peterson and call it a wash. Or add Alen Hanson, as I recommended, and look for the upside to manifest itself.

Mike Soroka (SP, ATL) 41% owned

It's always exciting to see a rookie pitcher excel in his first Major League outing. It's far less exciting when they fall back to Earth and get sent back to the minors a couple weeks later. Soroka wasn't terrible against the Giants, but four runs in four innings dampened a lot of the enthusiasm around him. He'll make for a great streamer on Saturday against the hapless Marlins and maybe again if he gets them a second time around on the homestand, but regression may again set in the next time he faces a team like Boston. There's a lot to get excited about in dynasty leagues with this homegrown talent, but at just 20 years old, he'll have some bumps and bruises this year and may not last in the rotation for long if he needs more seasoning. If you picked him up, wait until he performs well against the Marlins (presumably) and then sell for a safer, veteran pitcher who isn't at risk of demotion after one bad outing.

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