10 Fantasy Baseball Players to Buy and Sell for Week 6

Dylan Bundy is off to a hot start, but a look at his peripherals suggests he might be a prime sell-high candidate.

Well, we're five weeks in, which is one of the most important parts of the fantasy baseball season. Are hot starts legitimate signs of breakout performances? Are cold starts just a result of a small sample size, or are they warning signs?

For the most part, it's too early to overreact. However, you will find several owners ready to push the panic button already.

Perhaps you're one of these owners -- it happens to the best of us. If you're not sure whether you should hold or fold on a player, 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 ones warrant taking action on this early. Some may seem premature, but that is the goal -- to be ahead of the rest of your league.

Sell Dylan Bundy

Through five weeks of baseball, few pitchers have been better in fantasy than Dylan Bundy, who sports a 5-1 record and a sparkling 2.17 ERA. After years of waiting for the former top prospect to reach the Major League level, fantasy owners are all aboard the Bundy hype train.

However, a deeper look at the numbers suggests that there is some regression coming Bundy's way. Among starting pitchers with an ERA under 2.5, none has a worse strikeouts per nine innings rate than Bundy's 5.52 mark. The same can be said for his ugly 9.7% strikeout-to-walk differential, which ranks in the bottom third of qualified starting pitchers. Bundy's 4.63 xFIP and 4.73 SIERA suggest that there is some correction coming for his ERA as well, which is further backed up by his .256 BABIP against and 84.8% strand rate, both indicators of good luck.

This is the first time we've really been given an extended look at Bundy, so he could just be one of those pitchers who can outperform his peripherals. However, a more likely case can be made for his enjoying extraordinarily good luck thus far. Regression is likely coming for the injury-prone righty, so see if you can sell him at the right price.

Hold Carlos Santana

Carlos Santana is a perennial slow starter, boasting a career .782 OPS in the first half and .835 mark in the second half, according to This season has been no exception, as he has a .705 OPS. Is he just off to another slow start, or is there cause for concern?

Santana is a notoriously low BABIP guy, with a .268 career mark, but that number has been even lower this season, at .243. Another indicator of bad luck thus far is his 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. A look at xwOBA would suggest that Santana has been among the league's most unlucky hitters thus far, as there is a 33-point difference between his actual wOBA and his xwOBA.

Nothing has changed as far as Santana's approach at the plate -- he's still been one of the most patient hitters in the league, boasting a 12.1% walk rate and 9.1% strikeout rate. His contact rate is up to what would be a career-high of 89%, and his swinging-strike rate would be a career-low, at 4.3%.

Santana has been a hard player to own in roto leagues, where he has provided very little power and is a batting average and stolen base killer, but he should turn it around soon. He is coming off of a career-high 34 homers last season and is going to help you in that category before too long. He is a terrific asset in points leagues, where his walks and lack of strikeouts make up for his slow start at the plate. Don't give up on Santana based on a slow first few weeks -- he has too long of a track record for this to continue for much longer.

Sell Ryan Zimmerman

Ryan Zimmerman has been the fantasy darling of 2017, hitting .435 along with 13 homers, 28 runs, and a ridiculous 34 RBI. While he's probably not going to reach the 70 homers and 184 RBI he's on pace for, Zimmerman is absolutely crushing the ball, posting a 48.2% hard-hit rate, so just how far off are his current numbers?

Well, for starters, just two hitters have a larger discrepancy between their wOBA and xwOBA than Zimmerman, whose wOBA is 98 points higher than it should be, according to the metric. Even with that knowledge, it is worth keeping in mind that Zimmerman's xwOBA of .471 trails only Freddie Freeman for the league lead. His .472 BABIP is the highest in the league and a far cry from his career .312 mark. He also has the third-highest home run-to-fly-ball rate (39.4%), another indicator that his power surge is not sustainable while he's only putting 38.8% of balls in the air.

So, to sum it up, yes, Zimmerman is absolutely destroying baseballs. The underlying numbers back up the fact that his ridiculous pace is unsustainable, but we already knew that he wasn't going to launch 70 deep balls this year. Now that we are over a month in, you may be able to get someone in your league to buy in to what he has done thus far and overpay for the 32 year-old injury prone player who hasn't hit more than 20 homers since 2013. Make sure to sell him at the right price though. Don't just give him away because he is healthy right now and is raking.

Buy Jake Arrieta

Jake Arrieta followed up his other-worldly 2015 Cy Young performance with a respectable 18-8 record and 3.10 ERA last season, but he scuffled to the finish line, posting a 4.44 ERA over his final 16 starts and a 5.30 ERA over his final six. So, after watching him post a 4.63 ERA through his first six starts of 2017, many owners may be ready to push the panic button.

However, for the first time since being acquired by the Chicago Cubs in 2014, Arrieta has not outperformed his peripherals this season, actually appearing to be the victim of some bad luck. His 3.12 xFIP ranks 12th among qualified starting pitchers, but his ERA is the second-worst among pitchers with an xFIP below 3.50. A big reason for that discrepancy is the .333 BABIP opponents have posted against him, which is the 13th-highest mark among qualified starting pitchers.

In many regards, Arrieta has actually been better this season than in years past. His swinging strike (11.1%) is a career-high and his contact rate against (75.2%) is a career-low while his strikeout rate (27.9%) and strikeout-to-walk differential (21.8%) are both career bests as well. He should turn things around sooner rather than later and is an excellent buy-low option.

Sell Danny Duffy

Danny Duffy has been one of the most perplexing starting pitchers this season, as his results have been solid (3.50 ERA), but the way he has gone about reaching his numbers have not been what we grew accustomed to last season. His velocity is down quite a few ticks, as is his strikeout rate, which is down from 25.7% last year to 16% this season. Both are very concerning signs for the hypothetical upside of Duffy, who many liked as a preseason breakout candidate.

Duffy's 4.65 xFIP is actually one of the league's worst marks, ranking in the bottom-third of starting pitchers, while his 7.2% strikeout-to-walk differential ranks in the bottom 15.

After getting lit up in back to back starts, Duffy allowed just one run last night, and this may be one of your last chances to sell him based on the hype he generated heading into the season.

Buy Rougned Odor

There have not been many hitters more unlucky than Rougned Odor through the first five weeks, who, despite posting a nearly identical hard-hit rate as last year (35.1%), has just a .190 batting average and .381 slugging percentage. Well, when you look at his .198 BABIP -- the seventh-lowest mark in the league -- it isn't hard to see why Odor's base numbers are so bad.

No other player with a BABIP below .220 has a hard-hit rate as high as Odor's, and given a look at his career .285 mark, he should start seeing some better luck on balls put in play soon. He showed some signs of life at the plate last week, collecting five hits in his last five games, including a double and two home runs. He should get hot and enjoy some positive regression soon and return to the near-elite level of play he was at last season.

Sell Miguel Sano

Miguel Sano's hot start may have gotten a bit overlooked amid the ridiculous starts of Zimmerman and Eric Thames, but the slugger has been punishing baseballs through the first five weeks, posting the league's second-highest hard-hit rate and the highest average exit velocity. As a result, the elite power prospect has sent 8 balls into orbit and knocked in 28 runs through his first 29 games.

Given how hard he is hitting the ball, Sano's power seems legit. It wouldn't be surprising for him to end near the league lead for homers when it is all said and done. What is surprising is his .300 batting average, which appears quite misleading when taking a look at the underlying numbers. First off, his contact rate (65.9%) is right in line with his career numbers and is the seventh-worst mark in the league. No other player in the bottom-10 in contact rate have a batting average anywhere near .300. His strikeout rate (34.1%) is also right in line with his career numbers and is the league's seventh-worst mark.

Sano's bloated .440 BABIP trails only Zimmerman for the league-lead and, when viewed in conjunction with his low contact rate, is a clear indicator that there is some serious regression coming in terms of batting average. If you can get an owner to buy Sano based on his current numbers and pedigree as a former big-time prospect, do so now. He simply cannot maintain a batting average anywhere near .300 when striking out this often and a cold streak is coming soon.

Buy Danny Salazar

After a second-half collapse last season, Danny Salazar has posted just a 4.28 ERA through his first six starts of 2017, so many owners might not realize just how dominant his stuff has been to open the season. Despite not making it out of the seventh inning in a single start, the flamethrower has piled up at least six strikeouts in every start, good for a ludicrous 13.1 strikeouts-per-nine-innings mark -- the highest in the league. His 16.6% swinging strike rate also sits atop the leaderboard, while his 66.5% contact rate against is the lowest in the league. The dude has been straight filthy.

Salazar's xFIP of 3.22 would be a career best and isn't close to matching his 4.28 ERA. His xFIP ranks 16th among starting pitchers and makes him one of just three to have an xFIP under 3.5 and an ERA above 4. A big reason for Salazar's xFIP and ERA not matching up is the .385 BABIP his opponents have posted, which is the second-highest mark in the league.

Salazar may never be an efficient pitcher (he has a career-worst 4.28 walks per nine innings), but his stuff is good enough that he could post an ERA a lot closer to his mid-threes xFIP if he saw some better luck in the BABIP category. If he had an ERA in that range combined with his elite strikeout numbers, Salazar would be a highly sought after option in a depleted pitching pool.

Sell Mark Reynolds

Mark Reynolds has enjoyed a bit of a renaissance season thus far, hitting .321 with 11 homers for the Colorado Rockies. With Ian Desmond back in the lineup, most expected Reynolds would begin to lose out on playing time, but he is making his best case to remain in the everyday lineup, crushing three homers over his past three games.

While high BABIP and home run-to-fly-ball rates are the norm with Coors Field sluggers, Reynolds' .333 BABIP and 44% home run-to-fly-ball rate seem out of place when looking at his career marks -- especially the latter. Reynolds' 44% mark trails only the red-hot Aaron Judge, and makes him one of just eight players with a rate above 32%. Among those players, Reynolds (37.2%) is the only hitter with a hard-hit rate below 40%. When you combine that with his 29.1% fly-ball rate, it makes his 11 homers appear quite unsustainable.

A look at xwOBA suggests Reynolds is due for regression as well, as no player has a larger discrepancy between their wOBA and xwOBA. While Reynolds does have some power, he hasn't hit 25-plus homers since 2011, including just 14 in 118 games last season for the Rockies. He also is a career .236 hitter, so his .321 batting average is likely on its way down.

His underlying numbers suggest that a cold stretch is coming, and when it does, the Rockies will likely slide him into the part-time role that they envisioned for him heading into the season. Use the fact that he has seen regular playing time with Desmond back as a selling point and see what you can get for the aging slugger.

Buy Jonathan Lucroy

Jonathan Lucroy was almost certainly drafted as one a top-three catcher in all leagues, so it is fair to assume that his owners are frustrated by his complete lack of productivity. After posting a .292 batting average, along with 24 homers and 81 RBI last season, Lucroy is on pace for a .225 average, 10 homers, and 30 RBI this season.

While he hasn't hit the ball as hard this season, he is still seeing the ball quite well, posting the league's third-highest contact rate (91.3%). His swinging-strike rate is down to a minuscule 3.7% mark, while his strikeout rate is just 5.8%.

A big reason for Lucroy's slow start is his .219 BABIP, the 12th-lowest mark in the league, which is down from a career .308 mark. His xwOBA is also 30 points higher than his .277 wOBA, so there should be some positive regression coming there.

Lucroy is too good of a hitter to continue to struggle like this. If his owner is ready to cut ties with the proven slugger, buy-low now. If he starts swinging the bat like we know he is capable of, Lucroy is a very valuable asset amid a shallow catcher player pool.