Let's talk rookies. Let's talk waiver-wire adds. Lets talk disappointing youngsters and vets. We'll do all of that in the Mailbag. Here are some of the names we'll be discussing. Can you guess which category they fall into: J.D. Martinez, Jon Singleton, Steve Pearce, Joe Mauer, Devin Mesoraco, Oscar Taveras, Kole Calhoun, Alex Wood, Jesse Chavez, Jake Arrieta, Doug Fister, Justin Verlander, Cody Asche and my favorite, Mike Moustakas?

FIND OUT HOW TO GET ALL OUR INSEASON BASEBALL COVERAGE WITH THE ASSISTANT GM PRODUCT.

– J.D. Martinez or Jon Singleton? 
@Bigshot512

Wasn't it just a few weeks ago that everyone had to have Singleton on their roster? I don't mean to pick on the fellas who asked this question, but I will use it as a quick soapbox.

You can't win in fantasy baseball, not in a roto league anyway, if you do something like the following. You draft Allen Craig. He stinks. You add Chris Colabello. Then Garrett Jones. Then you go to Ike Davis, then you take a shot on Singleton. Now your going Carlos Pena. Folks, you have to make a choice on a player and stick with it. If you're constantly going back and forth, never letting anything settle, you're going to have a hard time winning. 

Singleton has been exactly what I said he would be in his Player Profile. A quote from that piece. “When you try to figure out what to do with Singleton you should have names like the following in mind: Ryan Howard, Mike Napoli, Mark Reynolds, Mark Trumbo and Adam Dunn.” He's hitting .188 with a .269 OBP. Here's his 150 game pace: .188-30-75-75. If he had three more hits he'd be batting .232, and what do you know, you have Mark Reynolds. This is who he is folks. Oh, and the strikeouts have been there, in spades: 26 in 20 games or one every 2.65 at-bats. Awful.

Martinez, a reserve round selection by yours truly in AL LABR, has been insanely good. In 37 games he's hit .314 with eight bombs and 29 RBIs. Sick levels of production. Issues abound though. (1) He's seen a lot of PT of late cause Torii Hunter has been out. He should still obviously find his way into the daily lineup while he's hitting like this. (2) His BABIP is .367. (3) His line drive rate is 24 percent. (4) His HR/F ratio is 24.2 percent. His first three seasons he didn't even reach 12 percent. (5) He's only walked seven times. (6) His first 899 big league at-bats he hit .251 with 24 homers. How often does a guy go from barely being able to hold a big league roster spot to being an outright superstar?

Given that Singleton isn't likely to get much better you can given Martinez a shot, but know that his average will regress and it's likely that his homer rate will pull back substantially. 

– Steve Pearce or Jon Singleton?
@diss72003

Here we go again.

Pearce is even worse than Martinez when you look at his track record. The 31 year old first appeared in the big leagues in 2007. Since then he's never appeared in 62 games or reached 160 at-bats in a season. Entering the year Pearce had 743 career at-bats with a .238 average, .318 OBP, .377 SLG and 17 homers. He's roundly been labeled, and with good reason, a Quad-A player (too good for the minors, not good enough for the big leagues). But so far this year he's looked like the second coming of Miguel Cabrera. Seriously. Check out his slash line in 138 plate appearances: .344/.406/.592. For his career Cabrera is at .321/.398/.567. Still, come on now. Pearce has a 22.5 percent K-rate, a five year high. His BABIP is .414. That's only .114 points above his career mark. He has a 26.6 percent line drive rate. That's only 30 percent above his career mark. He has an 18 percent HR/F ratio. That's only 100 percent above his 8.4 percent career mark. 

If you want to play the hot hand go Pearce. Truthfully, both guys are pretty close to one another in terms of ROTW outlook though know that Singleton likely has a longer leash than Pearce does with the Orioles. 

– Should I trade Joe Mauer for Devin Mesoraco? 
@MaxYedid

How awful is it to think that this is legitimate question? Mauer, who just might end up in the HOF if he can figure out what the hell is going on, is being outplayed by a guy not many even drafted this year in single catcher leagues. At this point you have to go Mesoraco. No question. He has 12 more homers, 18 more RBIs, 11 more runs and is batting .060 points higher, and he's accomplished all of that in 127 fewer at-bats. At the same time odds are still at least 50/50 that Mauer hits .320 the ROTW and Mesoraco .260 (the opposite of their current averages). Truthfully, Mesoraco might not even hit .260. His 23 percent line drive rate and .343 BABIP dwarf his career numbers (20.0 and .266). Only 1-2 guys each year approach the 29.8 percent HR/F mark he currently owns. His first three years the mark was 11.1, 10.0 and 10.0 percent. Is he literally going to triple that in 2014? No chance.

Can't go against Mesoraco since he's been so good, but there is no doubt a slowdown is coming. 

– Oscar Taveras or Kole Calhoun ROTW? 
@DerekKramolis

Again, I go with the known. Comparing the talent of the duo it's clear that Taveras is easily the option. If I was in a keeper/dynasty lg, I would totally side with Taveras. If we're talking 2014 go with the guy who has the role in the big leagues. Calhoun has really found his game in June as well batting .328 with three homers and 14 runs scored in 17 games. 

– Would you drop Alex Wood or Jesse Chavez for Jake Arrieta in 10 teamer? 
@AdiosTurdNugg3t

This is why I detest 10 team leagues. As I always say – if you want to do a 10 team league fine, but you have to add more roster sports to each squad to avoid having to make decisions like this. Wood is the most talented of the group. With the excitement of him returning to the Braves to take the rotation spot of the injured Gavin Floyd I can't see how you drop him. Even if you don't want/trust him (I do and do), then you can deal him for a pretty penny. Hold Wood.

Arrieta is one of the hottest hurlers in baseball. Through 10 starts he owns a 2.05 ERA, 1.11 WHIP, 10.11 K/9 and 1.83 GB/FB ratio. Those are Felix Hernandez numbers. No chance he maintains a one of them, but with the way he's pitching you simply cannot pass on adding him.

That means you drop Chavez. So let me ask you, those of you that play 10 team leagues, how do you defend a setup in which you are dropping a guy with a 2.71 ERA, 1.18 WHIP and 3.28 K./BB ratio?

– Should I trade Doug Fister for Justin Verlander 
@nick_sak

Verlander looked sharp in his last outing, but by any objective measure, since the start of the 2013 season, he's been a league average arm. He's been way worse than that this season. Do you know how bad he's been? Check out his numbers compared to a true flunky. 

J. Verlander: 4.82 ERA, 1.51 WHIP, 6.62 K/9, 3.61 BB/9, .280 BAA
Jake Peavy: 4.93 ERA, 1.46 WHIP, 6.75, K/9, 3.47 BB/9, .277 BAA

I'll go Fister. Steady, stable, solid. He's also pitching at a level that it's hard to envision Verlander getting to this year at any point: 2.65 ERA, 1.04 WHIP over nine starts. 

– Better ROS Mike Moustakas or Cody Asche? 

@ccopeland71

Really, I want to say neither. Not trying to be snarky. I'm going to hope this is a 15 team mixed league with corner infielders. If it's not you can do better. If that is what we're dealing with...

Moustakas is back to playing against most right-handers. I could care less. The dude stinks. He's so awful that when he bats .214 with four homers in a month, those are his June totals, that people get excited. Deep thoughts – he sucks like the worst tasting, foulest food you could think of. He is awful. For his career here is his slash line: .235/.289/.381. The average American Leaguer since 2011 is at .256/.321/.407. Why anyone cares about Moose astounds me. 

Asche is batting .273 with four bombs an a solid .348 OBP over 139 at-bats. He's actually been better than that though. Remove his first 22 games of action and focus on the last 22 and here's what you get: .329/.398/.544 with 17 RBIs. He's not a slugger, and he's not keeping that pace up, but the point is that he's settled in pretty nicely.

Go Asche. I just cannot stand Moose. 

You can follow Ray Flowers and send him your thoughts on Twitter @BaseballGuys. For up to the minute baseball reports on trades, injuries, lineups etc. see @FantasyAlarm.