10 Fantasy Baseball Players to Buy and Sell for Week 9

We're nearing the midpoint of the MLB season. At this point, most owners are reaching decision-making time regarding their teams.

Maybe your team has been plagued by injuries and it is time to cut bait on guys you would have preferred to hold onto, because you're in win-now mode. Perhaps you find yourself with a comfortable lead in the standings and can afford to take a chance on some buy-low players in hopes of a bounce-back heading into the later stages of the season.

Regardless of where your team sits right now, you should always be looking to take advantage of market inefficiencies on players.

Perhaps a slow start is just a product of bad luck and a small sample size. Maybe the reason you're in first place is due to the stellar but possibly unsustainable play of some players you can sell-high on. 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.

Sell Lance Lynn

Only two qualified starting pitchers have a lower BABIP against than Lance Lynn this season, who sports a .212 mark, which is quite a bit better than his career .302 mark. When viewed in conjunction with his 12th-ranked strand rate (83%), it should come as no surprise that Lynn's xFIP (4.22) doesn't match up with his ERA (2.93).

Nearly everything else about Lynn's profile -- strikeout rate (K%), walk rate (BB%), ground-ball rate (GB%), fly-ball rate (FB%), contact rate (Contact%) and swinging-strike rate (SwStr%) -- this season is right in line with his career averages, as you can see displayed in the table below.

Based on the numbers we've examined, regression in traditional numbers certainly seems headed Lynn's way. Once his luck runs out on balls put in play, there's a good chance he returns to a serviceable but unspectacular fantasy option. If you can sell him based on his sub-3.00 ERA through the first two months, do so now.

Hold Manny Machado

Owners of Manny Machado can't be disappointed in his contributions in the power department thus far, but his .220 batting average is far from his .280 career mark. Well, his .228 BABIP (15th-lowest in the league) goes a long way in explaining his early struggles with his batting average.

Only one other player with a BABIP below .230 has a hard-hit rate as high as Machado's 42.5% mark (which would be a career high). Joey Gallo sports a 43% hard-hit rate, but a big reason for his low BABIP can be traced to his inflated 61.3% fly-ball rate, as opposed to Machado's healthy 44.5% mark.

A great tool for finding hitters who are either underperforming or outperforming their talent is xwOBA, or expected wOBA. Expected wOBA uses exit velocity and launch angle to predict what the results of a hitter's swing should have been, independent of fielding. Among 211 qualified batters, only 14 have a larger negative difference between their xwOBA and their actual wOBA than Machado. In fact, Corey Seager is the only shortstop with a higher xwOBA than Machado's .414 mark this season.

All signs point towards Machado being the top-10 fantasy asset he was drafted as in most leagues. If you are an owner, sit tight as the batting average returns to near his normal levels. If you don't own Machado, see if his owner is ready to panic.

Sell Antonio Senzatela

Not far behind Lynn in the BABIP against category is Antonio Senzatela, who has seen his opponents post just a .249 BABIP against him this season. As such, the rookie sensation has been able to compile a 7-1 record and 3.19 ERA. However, his pedestrian 4.54 xFIP suggests there may be trouble ahead for the 22-year old who calls Coors Field his home stadium.

Only three pitchers have posted a higher contact rate against than Senzatela (86%) this season, which definitely is not a recipe for success for a Colorado Rockies pitcher. While it is nice that he is able to keep the ball on the ground consistently (46.6% ground ball rate), his inability to miss bats (14.7%) is a scary sign for Senzatela owners going forward.

If you've been riding Senzatela through the first two months of the season, it is time to start throwing some offers out there involving the rookie. With an injury-decimated starting pitcher player pool, you might be able to get someone to overpay.

Add/Buy Trevor Bauer

On the complete other end of the spectrum, we find Trevor Bauer. Despite posting an ugly 6.30 ERA, Bauer ranks 15th among starting pitchers in xFIP. A big reason for that is his .328 BABIP against and his uncanny inability to strand base runners. He's stranded just 64.8% of his base runners this season, the fifth-worst mark in the bigs.

For all of his inconsistencies this season, one thing Bauer has consistently done well is miss bats. He has struck out at least six batters in all but one of his starts this season and ranks seventh in strikeouts per nine innings (K/9) with a 10.62 mark.

A big reason for Bauer's inflated ERA is his early-season struggles. After a rocky start, Bauer hasn't allowed more than three runs in any of his past three starts, a stretch during which he has posted a 11.65 strikeouts per nine.

He's still available in nearly 80% of ESPN leagues, so there's a chance you can get him for free off your waiver wire. If he is owned in your league, see if you can buy-low based on his bloated ERA.

Sell Keon Broxton

Keon Broxton has appeared the part of a serviceable, high-upside fantasy outfielder through the first two months of the season, contributing in both the power (5 homers) and speed departments (10 stolen bases), while also chipping in a usable batting average (.261).

While those numbers don't jump off the page, there is reason to believe that Broxton is nothing more than a replacement level player who has seen extraordinarily good luck to begin the season. For starters, his .412 BABIP is the third-highest among qualified hitters and has helped fantasy owners ignore the fact that he has struck out in 37.7% of his at-bats. Once that BABIP drops to a more sustainable level, it will be very hard for Broxton to maintain his batting average if he is striking out this frequently. To add further fuel to the fire, Broxton's 63.5% contact rate is the third-worst among qualified hitters, which makes his batting average seem even more unsustainable.

Not only has Broxton struck out at one of the highest rates in the league, he is rarely drawing walks, posting just a 6.6% walk rate. If his BABIP does indeed drop, it is going to be very hard for Broxton to reach base with any consistency, which will in turn make it hard for him to contribute in his most important category -- stolen bases.

This isn't to say that Broxton can't be a useful player in fantasy, but rather that he isn't likely to continue to be the player he has been thus far. Everything about his stat profile suggests that he is more of a low .200s hitter than the .261 hitter he has been.

Buy Jake Arrieta

Jake Arrieta has been one of the most perplexing pitchers of 2017, posting an ugly 4.92 ERA in spite of a respectable 3.58 xFIP and 10.16 strikeouts per nine mark that ranks in the top-10 among qualified starters.

A quick look at his BABIP against and strand rate -- two of the stats most commonly associated with luck for pitchers -- offers some explanation for Arrieta's early-season struggles. Only seven pitchers have a higher BABIP against than Arrieta's .340 mark, while his 63.6% left on-base percentage is the third-lowest among qualified starting pitchers.

There are reasons for concern with Arrieta -- namely his dip in velocity thus far. He probably is never going to bounce back to the Cy Young award winner we saw in 2015. Nearly all of his underlying numbers are in line with last year's, though, when he posted a 3.10 ERA on his way to 18 wins. If you can afford to wait on him to turn things around, Arrieta profiles as one of the best buy-low targets in baseball.

Sell Miguel Sano

At this point, it is fair to wonder if Miguel Sano's hot start is just a breakout from an immensely talented slugger. I mean, the dude has a freaking 53.5% hard-hit rate and average exit velocity of 100 miles per hour -- both of which lead the league.

The power is legit. Assuming he stays healthy, Sano should find himself near the top of the league in both homers and RBI when the season ends. What doesn't seem legit is his .293 batting average, which conflicts with his league-leading 38% strikeout rate. Among the other players in the top-10 in strikeout rate, only the aforementioned Broxton has a batting average above .260.

Similar to Broxton, Sano has benefited from a unsustainably-high BABIP. His .467 mark is higher than any other qualified hitter and is due for some regression. Sano also has just a 63.4% contact rate this season, which is the second-lowest in the league.

This is not to say that Sano is not a legit power threat or useful fantasy asset, but rather that he is a prime sell-high candidate. Explore trade offers and see if you can get a leaguemate to buy him as a top-tier fantasy asset, because the batting average will likely come crashing down soon.

Add/Buy Devon Travis

Many liked Devon Travis as a post-hype sleeper heading into this season, but some extraordinarily bad luck saw him really struggle early on. Using the same xwOBA metric we used for Machado earlier displays just how unlucky Travis has been -- he has the largest discrepancy of any player between his xwOBA and wOBA. Travis has just a .196 wOBA this season despite a .324 xwOBA.

Travis' .289 BABIP through the first two months is also a 51-point drop from his career average.

He's seen some statistical correction over the past couple weeks, as he has posted a .449 batting average and .816 slugging percentage. He should continue to benefit from positive regression, and he is worth an add in the 60-plus percent of ESPN leagues in which he is still available. If he is already owned in your league, see if you can still fit in a buy-low offer based on his disappointing season-long numbers.

Sell Xander Bogaerts

After swatting a career-high 21 homers last season, Xander Bogaerts has just one dinger to his name through 45 games. He has made up for the lack of power with a stellar .331 batting average, which would easily be a career-best. In an increasingly power- and strikeout-heavy game, a lot of fantasy owners are craving a player who can post a high batting average, such as Bogaerts.

So, what's the problem? Well, Bogaerts' peripherals suggest that his inflated batting average is due for some regression. His .396 BABIP ranks seventh in the league and is sure to fall a bit. According to xwOBA, just three hitters have had better luck than Bogaerts, who boasts a wOBA nearly 100 points above his xwOBA. Quite simply, while he has hit the ball well thus far, he's also been aided by some good luck.

In addition to a batting average that is likely to fall, Bogaerts' power display from 2016 is beginning to look more and more like an outlier. He had never hit more than 12 home runs in a season prior to last year, and his hard-hit rate has hovered around just 30.0% over the last three seasons. He also has just a 32.3% career fly-ball rate, a number which is way down this season (23.4%). He currently has a 55.9% ground-ball rate that certainly isn't representative of a traditional power hitter.

Bogaerts showed in 2015 that he can be productive even when not being a power threat, so it would be silly to overreact to his numbers thus far and give him away for less than market value. However, you might be able to get someone in your league to overpay for him based on his impressive 2016 and bloated 2017 batting average.

Add Koda Glover

After being named the closer for the Washington Nationals, Koda Glover has fired 3 1/3 perfect innings while piling up five strikeouts and three saves.

He doesn't profile as an elite swing-and-miss guy, but he should have the opportunity to pick up saves in a hurry for the league's fifth-best team, according to our nERD metrics. Still available in over 50% of ESPN leagues, Glover is a must-add if you are in need of help in ERA, WHIP, or saves.