Also see:

• Fantasy baseball players coming of age - NL
• Fantasy baseball players in decline - AL
• Fantasy baseball players in decline - NL

Rare American League talents like the Tampa Bay Rays' Evan Longoria, only 24, have already reached elite form but have room to grow even further. Not all growers are this obvious, but those who had less noticeable progressions also deserve gold stars.

Players come of age at different paces, and these commodities are at different stages of their careers. Have they pretty much hit their full potential yet? Are they sniffing their peak?

Arrived

Robinson Cano, second baseman, New York Yankees

The already contact-friendly Rod Carew clone increased his rawhide-smacking percentage in each of the last two years, earning a firm place in the elite keystone tier. He experienced a power spike in his age-26 season that wasn't obscenely aided by Yankee Stadium.

Price increase in 2010?

Jason Kubel, outfielder, Minnesota Twins

The 27-year-old, already a blossoming power bat, showed baby-step improvement against southpaws, hitting .243 against lefties last year. He hit .300 overall in '09. Another full year in full-time duty should only help his quest to balance out these stats. Imagine his cumulative line if that happens....

Jered Weaver, starting pitcher, Los Angeles Angels of Anaheim

A bout with dead arm last year stunted his growth a bit, but he managed to sustain his ratios for the most part. His strikeout potential has probably reached its ceiling considering his velocity is nothing special, but he's crafty and knows how to vary his arsenal. Weaver has entrenched himself as a No. 4 mixed league starter.

In progress

Kurt Suzuki, catcher, Oakland Athletics

One of the best catcher draft values last year, Suzuki more than doubled his homer total from 2008, when his pop lagged while moving to everyday work. We'll see if he can avoid Russell Martinitis, but he hasn't had any major injuries in recent years.

Kendry Morales, first baseman, Los Angeles Angels of Anaheim

He was buried in a first base logjam in recent years and broke through when given his first chance. You'd like to see him do it again before confirming his maturity. Morales could do better against lefties, but he's close to putting things together.

Jose Lopez, second baseman, Seattle Mariners

What about this unheralded starter for the M's since '05? He had already earned recognition for providing isolated power from the second base slot before he jumped from 17 homers in '08 to 25 last year. He's establishing himself as a midrange option at second base and a suitable MI inhabitant.

Who can? Cano can

Adam Lind, outfielder, Toronto Blue Jays

This lefty stick used his 2007 and '08 springboards toward breaking out in '09, during which he turned 26. Along with improvement against southpaws, Lind learned how to take a walk last year, nearly doubling his '08 free-pass frequency.

Shin-Soo Choo, outfielder, Cleveland Indians

Choo, a five-category threat, shined in his first full season as a starter. He smokes line drives, which helps sustain offensive production; some of those line drives turned into bombs last year. His hard contact will come in handy if he can't slash his K totals.

Denard Span, outfielder, Minnesota Twins

Span, 25, rewarded the Twinkies for their patience. He kept a high-level BB/K of 0.79 in 578 at-bats last year after posting a 0.83 figure in part-time duty in '08. Partially as a result his contact rate increased to 89.9 percent from 88.7 - a positive sign that the nearly 26-year-old can grow further. He was a decent prospect at one time.

Jon Lester, starting pitcher, Boston Red Sox

After triumphing over cancer, Lester, soon to be 26, has nurtured his command ratio in his last two seasons and boasted an exploding 9.96 K/9 last season. His ailment may have stalled his dominance breakout; his off-speed growth ranks him as a low-end fantasy ace.

Matt Garza, starting pitcher, Tampa Bay Rays

This righty may have lost 12 games for the Rays in '09, but he regained confidence in his heat, thereby increasing his K rate. Sustaining his aggression came with some speed bumps in ERA and walks, but he has the talent and stuff to become a steady No. 2 fantasy arm.

On the cusp

Billy Butler, first baseman, Kansas City Royals

Butler's 51 doubles in 2009 may not stay that high for long, and that's a good thing for fantasy baseball owners: more home runs. His smart hitting shone through in the second half last year, in particular his work against righty throwers. He's also working on shaping up physically for 2010.

Ready to Lind a hand

Adam L. Jones, outfielder, Baltimore Orioles

He promised to swipe more bags before last season; instead he posted an insanely high BABIP in the first half before knee and ankle injuries halted him. He needs more lift in his swing, but the power-speed potential still makes us drool, especially if he can translate his scorching first-half bat throughout the year.

Max Scherzer, starting pitcher, Detroit Tigers

He needs to develop a third pitch, but the Tigs are willing to let him prove he's a starter, not a reliever. Scherzer, 25, didn't let an early-season shoulder injury throw his season off. The righty can bring the heat and the K's. Fine-tuning his control, keeping the ball down and gaining in-game efficiency will go a long way in Scherzer's maturity, but you can't deny his dominant future.

David Price, starting pitcher, Tampa Bay Rays

Sure, he has work to do, but many are giving up on him way too soon. He sacrificed dominance in the '09 second half but tried to learn how to pitch in the process. We can't expect a miraculous turnaround in the walks department, and the hype machine probably moved too quickly for him. An improvement in his pitch counts is Step 1 to moving the wheels again; once he learns to work around the plate, the K's should return.

Also see:

• Fantasy baseball players coming of age - NL
• Fantasy baseball players in decline - AL
• Fantasy baseball players in decline - NL