A full month of baseball is in the books. Every April a new crop of off-to-the-races, hot-starting players arises. Likewise a few perennial studs limp into May with below-average stats encouraging anxious owners to make hasty moves. What May indicates for "sharky" owners is opportunity to pounce on the weak and bolster their roster for the long haul.

Let's take a look at some potential Buy Low and Sell High opportunities that could score you a lasting investment in fantasy stardom. I will be using standard 5x5 scoring for ranking purposes and comparisons.

Sell High for a lasting return:

Jean Segura (SS, MIL) - A red-hot start (.358 BA, 3 HR, 14 R, 10 RBI and 8 SB) currently has Segura ranked as the #1(CBS) shortstop above the likes of Troy Tulowitzki, Starlin Castro and Asdrubal Cabrera. In 151 at bats last season Segura had zero home runs, 14 RBI and swiped 7 stolen bases. While Segura could mature into a very well rounded fantasy contributor he lacks the track record to back a 18 HR/62 RBI pace. Now is the time to cash in with Segura as a market correction is surely ahead.

Other over-performing shortstops: Brandon Crawford (Giants) and Marwin Gonzalez (Astros), but neither will not secure the return that Segura should bring.

Nate McLouth (OF, BAL) - The former Brave and Pittsburgh cast-off has turned in a stellar start to the 2013 campaign for the Orioles. It is likely too stellar to buy.  McLouth is currently the 10th-ranked OF in CBS scoring, ahead of Braun, Ellsbury, Trout, McCutchen, Kemp and a whole slew of surefire fantasy studs. He screams "sell right now," and holding on too long could cost you significant returns. If someone is hungry for OF help with steals and  runs, now is the time to pitch McLouth to them. SELL.

Other over-performing outfielders: Ryan Raburn over the past week and Carlos Gomez (.372 AVG / 3 yr avg .246)

Yuniesky Betancourt (1B/2B/3B, MIL) - A journeyman utility infielder who landed back with the Brewers due to injuries; Betancourt has turned a new-found patient approach at the dish into staggering offensive output. "Yuni-B" is tied with Ryan Braun for the team lead in HR (7) and RBI (22) with a .269 BA thus far. Apparently, while in winter ball Betancourt found a new approach and has turned it into a red hot start. He currently holds a .281 ISO (SLG minus AVG) which is well over his career ISO of .123 in seasons with more than 500 plate appearances.  His HR/FB% is at a ridiculous 20.6%, while it has never been above 8% in a full season. If you can score a slumping star in a package containing Yuniesky I would say the Market Value is as high as it will ever be on him. SELL.

Other notable players playing over their heads: Mark Reynolds batting .295, John Buck (everything screams "Sell!"), Daniel Nava, Justin Masterson, Clay Buchholz, Dexter Fowler, Mike Napoli

Buy Low and reap the benefits: 

Owners are less likely to sell-low on early-round/high-dollar injured players, so I will leave the likes of Giancarlo Stanton, Mark Teixeira, Jason Heyward and Brian McCann off this report for now. Lets take a look at some unusually slow starters who could be primed for a profitable bounce back.

Matt Cain (SP, SF) - Cain was the first name that popped into my head when I thought up this piece. He has shown steady improvement in every standard category over the past three seasons, showing a drop in ERA and WHIP and a slight climb in strikeouts. So what's with the early struggles? The most alarming stats that jump out at me are his wicked high HR/FB at 19.1% which has never been above 9% in his career, and a very high HR/9 at 2.34 (career avg 0.76). What does it all mean? He's been one unlucky dude. Digging even deeper, Cain's strikeout rate is right where it should be, as is his walk rate. He's throwing strikes just as ever, but they're getting hit. Maybe he's tipping pitches? Maybe his movement is down with his minor drop in velocity. His SwStr% is down from last year's 9.6% to 8.3%, so his strikes are not missing bats as often, but we have every reason to believe he will turn it around. If you are ever going to try to make a play for Cain, now is the time!

Pedro Alvarez (3B, PIT) - "El Toro" is one of the streakiest offensive players in baseball. His hot streaks can amaze with power numbers galore, but his cold streaks are unbearably abysmal amassing lots and lots of strikeouts. He ended April with a modest hot streak and actually has managed to get his average up to .193. He has 5 long balls and obvious 30-HR potential. If you drafted him, you knew the risk; some owners however may be regretting that risk and they are prime candidates for a "sharky" Buy-Low. If you wait for him get hot one more time you may be too late to nab an extra 25 HR-- make your offers now.

Asdrubal Cabrera (SS, CLE) - You may have already missed your chance at this guy. With 4 straight games this week earning at least 1 RBI (and a total of 7 RBI over 4 games), Asdrubal may be finally warming up to 2013. It has been unseasonably cold everywhere and that could have been the culprit. He also had been dealing with a sore quad muscle in late April. He began the season batting just .127 with 17 strikeouts in  his first 55 at-bats. After back-to-back All-Star campaigns the past two seasons, Cabrera should be a prime target for a super finish to the season. He has 20+ HR potential and you could still potentially steal him away from an owner looking for a quick fix.

Other notable slow starts: Ike Davis (1B, NYM), Josh Reddick (OF, OAK), David Murphy (OF, TEX), Aaron Hicks (OF, MIN), Josh Hamilton (OF, LAA), Ben Revere (OF, PHI), Eric Hosmer (1B, KC), Jesus Montero (C/DH, SEA), Ian Kennedy (SP, ARI), Stephen Strasburg, Gio Gonzalez and Dan Haren (SP, WAS)

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