New kids on the diamond

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I never thought I would be repeatedly writing about underrated rookies. Most seasons, the kiddies are entirely overhyped, overdrafted and overvalued. Times are changing.

As I wrote last week regarding Carlos Santana, Pedro Alvarez isn't getting enough love. Nicknamed "El Toro" (the bull), Alvarez came to the bigs last week more like a lamb than a charging bull. Need proof? Alvarez is only owned in 15-percent of Yahoo! leagues. The Pirates new starting third baseman deserves much more fantasy attention. In 242 Triple-A ABs, the 6-3, 225-pounder had a .277 batting average, 13 home runs, and a .533 slugging percentage. In addition, as indicated by his 12 percent walk rate in the minors, Alvarez knows how to exercise plate patience. Sure, he compiles a fair amount of strikeouts (68 at Triple-A), but that usually comes with the power party.

Let's be honest, if it wasn't for the arbitration clock issues, Andy LaRoche would have been behind Alvarez for infield fielding practice in April. Alvarez has the tools to be a Top 15 third baseman for the rest of 2010 despite that weak ownership rate. He's certainly worth a pickup if you're relying on Ty Wigginton or Kevin Kouzmanoff in the second half. Snatch Alvarez for his power alone.

Dayan Viciedo (3B, CWS)

The White Sox would have preferred to give the 21-year-old Viciedo more time in the minors. Nevertheless, the injury (fractured finger) to Mark Teahen forced their promotion hand. Viciedo was hitting .290 with 14 HRs and a .514 SLG at Triple-A. He was smoking before his promotion with a .351 BA, three HRs, and .547 SLG in June. That said, I have an embargo against allowing this Cuban import on any of my starting squads in '10 -- even in AL-only leagues. Viciedo's putrid 3 percent BB rate and .15 strikeout-to-walk ratio scare the hell out of me. He will pop some bombs on the South Side, but an extremely low batting average and a whopping number of whiffs will follow. Stay away unless you have an AL-only team that is ravaged by injuries.

Chris Johnson (3B, HOU)

Pedro Feliz would make a sweet designated fielder. Unfortunately, despite Feliz's lobbying efforts, the all-powerful Bud Selig hasn't gone that route. As a result, Johnson was summoned from the minors to take over third base for the struggling (.220 BA, two HRs) Feliz. Now this is a young infielder I really like. The 25-year-old Johnson has the minor league experience (1,813 minor league plate appearances) and contact skills (.329 BA, 85 percent contact rate at Triple-A) to have an immediate impact in NL-only leagues. He's always been underrated because he doesn't have light-tower power, but that doesn't mean he can't be a fantasy asset. Make a play for Johnson in mono-leagues and monitor him in our weekly rankings.

Jason Castro (C, HOU)

I've been hammering this guy for two years; I won't stop now just because he was promoted on Sunday. Castro was hitting .261 with four HRs and a .351 SLG in a hitting-friendly environment at Triple-A. Yep, those are the type of numbers that earn you a promotion when you're in Houston's organization. The 23-year old has shown very limited power at advanced levels and his batting average has been in a continuous free-fall since High-A. Castro will have some value in NL-only leagues because of his ability to take walks (13-percent BB rate at Triple-A) and make contact (84 percent contact rate at Triple-A). Nevertheless, most of his value comes from name recognition because he's a former first-rounder. Take advantage of that fact if you're already a Castro owner.

Jonathon LuCroy (C, MIL)

Even though LuCroy has been up for a month, his value is just now beginning to rise. Brewers manager Ken Macha said last week that LuCroy will begin to see the majority of the catching duties over George Kottaras. Wise move, Mr. Macha. For some reason, Macha's vote of confidence for LuCroy has gone largely unnoticed in fantasy circles. LuCroy is hitting .341 since his promotion and .353 over the last seven days. He's surely a serviceable option in deep mixed leagues or two-catcher formats.

Desmond Jennings (OF, TAM)

Jennings hasn't lived up to expectations this year, but that doesn't mean you should forget about him. Specifically, Jennings is hitting .273 with zero HRs, a .355 on-base percentage, and .391 SLG. Jennings missed time at the beginning of the season with both wrist and shoulder issues. It has taken time for him to find his swing and get healthy. In June, he posted an impressive .313 BA, .373 OBP, and .493 SLG line. I will also point out that Jennings has stolen 16 bases on the year and has only been nabbed once. His SB ability will make him an impact mixed-league option once he's promoted. Jennings will find his way into Tampa Bay's lineup in the second half. Stash now.

Edinson Volquez (SP, CIN)

As I mentioned in Root's Rants last week, Volquez has the opportunity to repeat Josh Johnson's post-Tommy John surgery magic from '08. In eight rehab innings at High-A, Volquez has struck out seven and has not given up a run or a walk. Most importantly, he's hitting 92-96 mph on the gun. This is the same guy who posted a 3.21 ERA and 9.46 strikeouts per nine in '08; there's upside here. Volquez is only owned in 11 percent of Yahoo! leagues. Electric and proven arms like Volquez are rarely waiting for you on the waiver wire. Grab him now before the masses catch on; Volquez's scheduled July 7 return is only a few weeks away.

Brandon Allen (1B, ARZ)

Allen has fallen off the radar because he's only batting .250 with six HRs and a .464 SLG. I'm still a big-time believer. Allen has focused on improving his pitch recognition skills this year and it's worked. He has amped his BB rate up to 21 percent; his new-found patience will only benefit him in the long-term in combination with his massive power. There's a strong possibility the Diamondbacks deal Adam LaRoche if they continue to rot at the bottom of the National League West. At that point, Allen would be given another shot to prove himself. I'm confident this year's audition will go better than his '09 stint (.202 BA and 40 strikeouts in 104 ABs). Of course, that's not saying much. The 6-2, 235-pound slugger is an undervalued long-term investment.

Kyle Drabek (SP, TOR)

Seriously, you have to feel a little compassion for Drabek. After being acquired in the Roy Halladay deal, Drabek is under a microscope in the minors. The 22-year-old has handled the pressure well at Double-A. In 84 IP, he has a 3.11 ERA, 7.18 K/9, and .236 batting average against. Drabek's power curve and ability to induce grounders (1.63 ground out to air out ratio) make him a solid target in keeper leagues. He will only make his debut this year if injuries strike the Jays' starting staff.

All statistics as of June 20, 2010.

Hit Bill Root with a tweet @Bill_Root or an e-mail at broot@rotoexperts.com if you have a burning fantasy prospect question. Make sure to check out our Xclusive Edge Rankings for help with your tough lineup decisions.