10 Fantasy Baseball Players to Buy and Sell for Week 8

We're seven weeks into the MLB campaign, one of the most important segments of the fantasy baseball season. Now is the time we ask important questions.

Are hot starts legitimate signs of breakout performances?

Are cold starts a result of a small sample size? Or are they warning signs?

Listen, regardless of the answers, it's way too early to overreact. Don't make a move just to make a move. But if you're not sure whether you should hold or fold on a player, don't sweat it. That's why we're here.

The following 10 players have seen a perceived change in their fantasy stock, and we'll attempt to decipher which warrant taking action. Some moves may seem premature, but sometimes premature is okay if it keeps you ahead of your leaguemates.

Buy Kyle Schwarber

Many fantasy owners were hyped for Kyle Schwarber following a breakout rookie season but were left unfulfilled when he missed nearly the entire 2016 season due to injury. After waiting all this time, it's fair to say that Schwarber owners are not satisfied with his 2017 output, as the outfielder has a .182 batting average through the first seven weeks.

There is a sliver lining, though: Schwarber's peripherals suggest that better times may be ahead. For starters, he has just a .229 batting average on balls in play (BABIP) thus far, which ranks in the bottom-20 among qualified batters this season. That's in spite of a 36.3% hard-hit rate, a number which has sat at 50% over the past two weeks. Despite destroying dozens of unsuspecting baseballs since opening day, Schwarber has just a .148 BABIP during this span, which is lower than any hitter with a hard-hit rate above 40%.

In addition to crushing the ball consistently, Schwarber has exhibited improved plate discipline and is on pace to finish with career bests in contact rate (76.4%), swinging strike rate (10.2%), and pitches swung at outside the zone (27.9%).

All in all, Schwarber's approach at the plate appears to have improved, and he's hitting the ball quite well. The early struggles in the batting department could well be the result of some bad luck on balls put in play, and he should soon give you positive return your draft day investment.

Sell Willson Contreras

While Schwarber has shown the same approach at the plate that made us fall in love with him as a prospect, the same cannot be said for his Chicago Cubs teammate, Willson Contreras. Contreras has looked straight-up lost at the plate at times this season, as evidenced by his 67.1% contact rate, the eighth-lowest mark in the league. That's just the beginning, though.

Contreras has been worse in almost every facet of his offensive game this season. He's walking less (down from 9.2% of the time last year to 7.5% this season), striking out more (up from 23.7% to 27.6%), and swinging at a whole lot of air, as quantified by his 15.9% swinging strike rate. He's also managed just a 29.1% hard-hit rate, the lowest among qualified catchers, while also putting together the lowest fly-ball rate (27.4%) and the highest ground-ball rate (56%) among said qualifiers.

If you drafted Contreras, you likely took him as a top-five catcher. After watching nearly two months of baseball, though, it's becoming more and more apparent he's not that guy. Luckily, catcher is a shallow position in 2017, so you may still be able to convince somebody in your league to pay near full-price on Contreras, if only on name value.

Buy Matt Shoemaker

After being a trendy sleeper pick in fantasy this season, Matt Shoemaker struggled through his first seven starts, compiling an ugly 5.21 ERA. In his past two starts, he's allowed just 3 earned runs in 12.1 innings, while racking up a 11.68 strikeout-per-nine-innings mark that raised his season number to 8.94.

It's easy to dismiss this mini-streak as two well-timed quality starts, but when a pitcher Shoemaker's ability (don't forget that he put together a 2.83 ERA over his final 20 starts in 2016) begins to show flashes, it's worth examining.

What made Shoemaker so effective in 2016 was his use of the splitter, a pitch which he threw 35.7% of the time. He only threw his most effective pitch 26.9% of the time through his first seven starts of 2017 but seems to have regained his confidence in the pitch over his past two outings, mixing it in at a 34.1% clip.

While it seems silly that the drastic change in outcome could be as simple as throwing his best pitch more often, the results over the past two seasons back the theory up. With a two-start week on the horizon for Shoemaker, this may be your last chance to buy low.

Add/Buy Devon Travis

There are few players in the league who've been unluckier than Devon Travis. The statistics agree.

A couple of great stats for finding hitters who have either underperformed or outperformed their talent is expected weighted on-base average and weighted on-base average (wOBA). Among 211 qualified batters, no batter has seen a bigger difference in their wOBA and expected wOBA, which is based on exit velocity and launch angle, than Travis, who has a wOBA of .196 but an expected wOBA of .324.

Over the previous week, Travis has begun to experience a bit of the positive regression that was somewhat expected, compiling a .536 batting average and .929 slugging percentage over his past seven games. As hard-hit balls find holes in the defense with more regularity, the numbers should continue to pile up for Travis. The window either to add or buy low on him in deeper leagues is closing quickly.

Sell Ervin Santana

You're probably sick of hearing me go on and on about how Ervin Santana is outperforming his peripherals. Well, over the last couple of weeks, regression seems to be catching up with him, as he delivered a 4.95 ERA over his past three starts, in two of which he allowed five or more runs.

Despite his recent skid, Santana's ERA sits at a sparkling 2.07, the fourth-best mark among starting pitchers. However, his 4.77 expected fielding independent pitching (xFIP), a category in which he ranks bottom-20 among 94 qualified starters, tells a much different story. The discrepancy between his ERA and xFIP are easily explained by his league-low .143 BABIP against and league-high strand rate (90.7%).

Thus far this season, there hasn't been a starting pitcher more fortunate than Santana. You might not be able to sell him for what you could have a couple weeks ago, but given his lofty season-long numbers, you might still be able to net yourself more than what he's worth.

Buy Jeff Samardzija

On the opposite end of the spectrum, we have Jeff Samardzija, who possesses the league's fourth-best xFIP (2.85) but a 4.57 ERA. He's the only pitcher in the top-10 of xFIP to sport a losing record -- he's 1-5, somehow -- while also being the only to put up an ERA above 4.00.

Only four starting pitchers have more strikeouts than Samardzija, who has been absolutely mowing them down, at a clip of 10.48 strikeouts per nine innings.

He's also coming off 8 innings of shutout ball against the St. Louis Cardinals and now boasts a 2.73 ERA and 10.92 strikeouts-per-nine-innings mark over his past four starts. Similar to Travis, it appears his peripherals are synching up, so be sure to get in any buy-low offers you have now because his numbers probably aren't going to look this bad for much longer.

Sell Jake Lamb

Jake Lamb has been one of the most exciting breakout players of 2017, posting a .288 batting average and .942 OPS, numbers he backed up with an impressive 40.6% hard-hit rate. Does that sound familiar? Well, if you played fantasy baseball last season, it should.

In 2016, Lamb put up a .291 batting average and .983 OPS prior to the All-Star break, before collapsing during the second half to deliver a .193 batting average and .651 OPS. With his hot start this season included, here are how his first-half versus second-half numbers line up.

The fact that he's a first-half-of-the-season wonder could account for his inflated .358 BABIP, and it makes Lamb's ascension to the upper ranks of fantasy third baseman seem unsustainable. Don't give him away, but if you can get value that reflects his current level of play, go for it.

Add Corey Knebel

Corey Knebel has taken over the closer job from Neftali Feliz for a Milwaukee Brewers team that sits atop the NL Central. Since being promoted, Knebel has been dominant.

He's currently is riding a 13-game scoreless streak and has racked up an absurd 15.55 strikeouts-per-nine-innings mark and a career-best 13.1% swinging-strike rate. Opposing batters have also made contact on just 67.3% of their swings, which is easily a career-best, and ranks among the bottom 10% of 187 qualified relief pitchers this season.

Knebel is still available in over 50% of ESPN leagues, so if you need help in saves, ERA or strikeouts, be sure to give your waiver wire a look.

Buy Matt Carpenter

Matt Carpenter is riding a .235 batting average, so it might come as a surprise to see him in the "buy" column. A deeper look at his numbers, however, suggest that his average doesn't tell anything close to the whole story.

Carpenter has been even more effective over the past two weeks, compiling a hard-hit rate of 54.8%, the highest mark of any eligible second baseman. In spite of this, he has just a .212 batting average over his past 14 games, thanks to a dreadfully unlucky .172 BABIP. No player ranked in the top-35 in hard-hit rate over the past two weeks has a BABIP as low as Carpenter's.

As a career .282 hitter, Carpenter's struggles in the batting average department will likely only keep up for so long. If you can buy him now, make it so...especially because he's currently on pace to swat a career-best 36 homers.

Sell Zack Cozart

If we want to use expected wOBA to label Devon Travis as MLB's unluckiest hitter, we could use it to deem Zack Cozart the league's luckiest. No player has seen a more bloated wOBA than Cozart, whose wOBA is 100 points higher than his expected wOBA.

As part of a shortstop pool that includes a banged up Trevor Story, Troy Tulowitzki, and (potentially) Manny Machado, as well as a struggling Jonathan Villar, there may be a decent market for a player like Cozart. After all, who wouldn't want a shortstop hitting .351?

The truth is, Cozart hasn't been nearly the player that his base numbers suggest. In addition to an inflated wOBA, Cozart has the league's eighth-highest BABIP (.400) and the second-lowest hard-hit rate (33%) among players in the top-10 of BABIP.

Cozart is definitely a player who should be owned in all leagues, but if you can sell him as more than a replacement-level option, you should make your best effort to do so before regression catches up to him.