All prospects not made the same

Here's the great thing about prospects in fantasy baseball: There is always another one on his way. Or, even another few.

If you missed out on Mike Moustakas, Anthony Rizzo, Dee Gordon and Jemile Weeks last week, there is still Dustin Ackley and Desmond Jennings to resort to. Heck, the promising early returns of those four last week might even lure teams to consider the likes of Jesus Montero and Mike Trout.

And then there are retreads such as Ian Stewart and Travis Snider -- or the injured, but ready when healthy, Brett Lawrie (fractured hand). Those first two might be even more important than those that haven't failed yet in the major leagues.

Those are the very reasons you don't break your bank on prospects in leagues with FAAB (free-agent acquisition budget) this time of year. Sure, Moustakas and Rizzo look like a million bucks early. But if you miss out on one player, get the next one. Most of them carry similar upside -- and uncertainty.

There is no such thing as a can't-miss prospect. Ask Stewart and Snider.

Prospects are best served to fantasy owners as sleepers on the cheap. Overpaying for one of them can just lead to him going bust on you and setting you right back to where you started: Looking for who's got next.

Yes, we're sorry this annual warning should have come far sooner this season. But it is telling now. There are still plenty of first-timers on their way.

Here are the remaining ones on the cusp of arriving before the Futures Game in July:

1. 2B Dustin Ackley, Mariners (40 percent ownership)

Stats: .300, nine homers, 34 RBI, 56 runs, seven steals, .418 OBP, .487 SLUG

Ackley, frankly, belongs in the major leagues already. The second overall pick in the 2009 First-Year Player Draft to one Stephen Strasburg -- if there is ever someone to be picked second to, he's it -- has been on a tear in Triple-A.

If really wasn't a question of if Ackley would hit, but when and where he would. The answers are now and as a fantasy second baseman.

The latter is the most intriguing part of his value. Second base remains one of the thinnest positions in fantasy and Ackley looks like he could become a future No. 1 at the position.

Ackley not only has developed power this season, but he has also proven to be a North Carolinian God of Walks. He has walked 55 times and struck out just 38 in 65 Triple-A games (267 at-bats). That ratio has been amped up by 15 walks to just five strikeouts in 12 games in June.

Clearly, Ackley is too good to be down in Triple-A any longer. He can lead off for the Mariners right now. Just think of all those plate appearances and on-base chances in front of a resurgent Ichiro Suzuki. Wowser.

Add him immediately in any fantasy league. He is available in 60 percent of them. And, best of all, he could be up in Seattle this weekend or by next Monday, according to the Seattle Times.

2. OF Desmond Jennings, Rays (40 percent)

Stats: .282-9-29-47-12 (.377-.469)

First it was Carl Crawford had to leave via free agency. Done.

Then it was the signing of Manny Ramirez and Johnny Damon. Ramirez is out of the way, retiring after another positive test result.

Afterward, TheLegendofSamFuld stepped forward. That has become more of a Legend of the Fall lately.

Now, it's Justin Ruggiano's streak (.372-3-9-5-1, .404-.628).

External forces just keep Jennings from making his official arrival in Tampa Bay. Still, Jennings points to himself making it happen.

"I didn't play well in spring," he told MiLB.com. "I don't know if signing those other guys had anything to do with it, but I didn't have a good spring -- and that's the reason I'm here."

Here is Durham, the famed stomping grounds of one Nuke LaLoosh on the way to "The Show."

"I would think he was disappointed when he didn't make the club, but he knows he's got to wait for his chance," Triple-A manager Charlie Montoyo told MiLB.com "But he also knows he's going to get a chance."

Jennings is making it happen himself, Fuld or Ruggiano notwithstanding. He has added the anticipated power to go with his speed and defense.

"Last year he battled through a shoulder injury," Montoyo said. "This year he's healthy and he looks a lot better. This year he can get to the inside corner better. His power numbers are better because he can get the bat through the zone better."

The power tends to be the last tool to reveal itself. It is the one that can make Jennings an impact hit in all fantasy formats, not just Rotisserie leagues.

"I've been more aggressive towards the ball," Jennings said. "Last year I was tentative in swinging at some pitches, but now I'm feeling good about letting it go and taking an aggressive swing. Last year I was just trying to put it in play. Now I'm trying to drive the ball and get some things going."

He will be getting things going in Tampa Bay before long.

3. 3B Ian Stewart, Rockies (13 percent)

Stats: .320-10-27-20-1 (.426-.701)

We have seen this show before. Stewart has been on the Triple-A shuttle this season due to injury and major-league struggles. But he always goes back down, proves healthy and then gets scorching hot.

The Rockies are underwhelmed by Ty Wigginton's defense at third base right now, so Stewart could get the call once again soon. Stewart is a superior defender and he should be a superior bat.

Stewart is just 3-for-47 in the major leagues this season, but he will levy some big-time payback. Promise.

It is time to buy back into the 26-year-old potential star.

4. OF Travis Snider, Blue Jays (20 percent)

Stats: .315-2-25-32-7 (.385-.449)

You might be loving what Ruggiano is doing for your fantasy team right now. You might even be anticipating the arrival of Jennings with him on your reserves -- or reaping circumstantial rewards from Toronto's Corey Patterson.

You should be stashing Snider instead.

Like Stewart, Snider has shown flashes of brilliance in the majors -- only to struggle at times and need this demotion. Like Stewart, he has gone down and taking the advantage of the opportunity to get hot again.

Unlike Stewart, Snider is just 23 years old. This is something very easy to forget, because he has been bouncing around the fantasy waiver wire for parts of three seasons.

Snider is hitting .395 in his past 10 games and is finally driving the ball again. He is slugging .596 in 47 June at-bats.

5. C Jesus Montero, Yankees (29 percent)

Stats: .292-5-25-20-0 (.338-.421)

Montero isn't necessarily ready offensively or defensively, but the Yankees might consider calling up their top hitting prospect to fill in at catcher if Russell Martin (back) needs to go on the DL in the coming days. The Yankees would only call up Montero if he can play every day and that seems more possible with Martin out right now.

Jorge Posada has kicked his slump and is hitting .444 (16-for-36) in June. Posada can catch in Martin's absence, but that leaves a vacancy at DH, too.

Montero will only be up for a short period while Martin is out, so consider Montero only a short-term option.

Honorable mention: OF Mike Trout, Angels (24 percent)

Stats: .330-8-22-50-23 (.434-.565)

Who doesn't want to be 19 again? Or even for the first time, for you young'uns.

Trout.

If not for his teen age, he could be a candidate to help a struggling Angels offense in the near future. The problem is he doesn't turn 20 until August.

There have been teen-aged hitters in the major leagues before, but Trout's promotion will likely be to Triple-A and no Anaheim in the coming weeks. He is almost certain to remain in the minors until after his 20th birthday.

Eric Mack chimes in on potential impact rookies and prospects every Wednesday at SI.com. If you have a prospect you want to see highlighted, let him know. As always, you can mock him, rip him and (doubtful) praise him before asking him for fantasy advice on Twitter @EricMackFantasy. Hit him up. He honestly has nothing better to do with his free time.