Harris Yudin looks at five players off to a fast start, who can be sell high candidates for fantasy baseball. They are fast starters who will may start to fade.

As mentioned here, it can be quite easy to overreact to a player’s early season production— or lack thereof. While some players take time to adjust to the new season, others explode out of the starting gate, only to fade away as time passes.

These five players often play their best baseball in April, and are worth selling or even dropping before the tides turn.

Let's get to it.

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Time to Sell High and Cash In?

Starlin Castro (2B, NYY)

It seems every year Castro turns heads in April, providing owners with hope that he will finally produce for an extended period of time. Still, he has surpassed a .315 wOBA just once in the last four years. Castro is a career .281 hitter, but that number sits at .321 in April. In 2016, he posted an April OPS of .833, exactly 100 points higher than the final product. Now, three weeks into the 2017 season, the 27-year-old boasts a .357/.400/.571 slash line to go along with four long balls. Castro is unlikely to maintain anything close to this pace, so now would be a good time to flip him for something valuable.

Mike Moustakas (3B, KC)

Moustakas hit .356 with a .942 OPS and a .410 wOBA in the opening month of the 2015 season, only to finish at .284, .817 and .353, respectively. Then, in 2016, he managed a .913 OPS with seven homers in April before a knee injury ended his season in early May. The 28-year-old slugger is off to yet another hot start in 2017, with six bombs and a .916 OPS through 17 games played. Moose could very well be turning the corner, but even if he cashes in a 30/.275 campaign — an improvement from any of his previous seasons — he’d still have to slow down from his current pace.

Zack Greinke (SP, ARI)

The former Cy Young Award winner boasts a dazzling 2.71 ERA throughout his career in March/April, falling above 3.00 in each of the next four months. While this hasn’t been the trend in either of the last two years, 2015 and ’16 were major outliers for Greinke, whose 2017 production will almost definitely fall somewhere in the middle. Following an eight-inning, one-run gem against the — admittedly hapless — Padres, the 33-year-old owns a 3.28 ERA and a 3.04 FIP, but also just a 19.8 percent strikeout rate and a career high 38.7 percent hard hit rate. Greinke is still deserving of a roster spot in all formats going forward, but he is certainly worth dangling in front of your league-mates.

Gio Gonzalez (SP, WAS)

Once a Cy Young candidate, Gonzalez has become one of the more inconsistent arms in baseball. Last year, he took a 1.42 ERA into May, but proceeded to allow at least five runs on eight different occasions over the rest of the season, finishing at 4.57. This isn’t a new trend— Gonzalez’s career ERA in April is 3.08, by far his lowest of any month. He owns a 1.35 ERA to begin the 2017 season, but at age 31, it’s becoming increasingly unlikely that the southpaw puts together a full, productive season.

David Robertson (RP, CHW)

Robertson has been one of the more reliable closers in the league over the last few years, but he doesn’t necessarily dominate from start to finish. The 32-year-old has yielded just two runs in his last 31 innings in April, dating back to 2014. However, he hasn’t finished with an ERA below 3.00 in any of those seasons, and it’s hard to believe this year will be any different. In order for Robertson, who has let up just one run in 6 2/3 frames this season, to reach the mid-3.00 range, he would have to post an ERA north of 4.00 the rest of the way. Ship him off before he starts his decline.

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