Adrian Cardenas, 2B, Athletics (Double-A Midland)

The big bat acquired from Philadelphia last year in the Joe Blanton deal, Cardenas entered the year with a career batting average of .299, a full .001 below expectations, as one scout had classified him as “the kind of player who seems like he could hit .300 in his sleep.” He’s doing much more than that early in the new season, going 3-for-4 with a home run on Friday, adding two hits (both doubles) on Saturday, and wrapping up the weekend with three hits, including a triple, to complete an 8-for-14 weekend that brought his average up to .405 over the first ten games of the year. With Mark Ellis signed through 2010 with a club option for ’11, it’s hard to figure out where he fits into Oakland’s future at his more natural position of second base, but the A’s have time to figure those kinds of things out… and a massively talented system is going to create a number of similarly difficult decisions over the next few years.

Gerrit Cole, RHP, UCLA

A few especially masochistic Yankee fans have been following Cole’s college career at UCLA, and one recently e-mailed me to ask what went wrong in the negotiations that kept the club’s first-round pick from last June from signing. The truth is, nothing really went wrong, the kid just had a change of heart-as any parent would explain, trying to gauge an 18-year-old’s emotions is a difficult thing. Still, the regret is understandable, as Cole has stepped into UCLA’s Friday starter role (the college equivalent of an ace) and not missed a step, striking out a career-high 13 against Washington on Friday while allowing only one hit over eight innings. With nearly twice as many strikeouts (71) as hits allowed (36) in 51 1/3 innings, Cole is lining himself up for a top five selection in 2010, so the Yankees won’t even have a chance to take him again.

Brandon Erbe, RHP, Orioles (Double-A Bowie)

The Erik Bedard trade netted Chris Tillman, while the last two drafts brought Jake Arietta and Brain Matusz into the system. That trio gets all of the attention, but Erbe was the best arm in the organization before all of that happened. He’s had his fair share of control issues since, but he’s still an outstanding arm, and that was on display Friday night, when he limited Akron to just one hit over six innings while striking out six in his second career Double-A start. While it seems as if he’s been here for a while, he’s actually just 21 years old, but he’s already delivering 92-94 mph heat, touching 96 and showing a much improved changeup to go with his average breaking ball. He’s just a small step below the big three, and there is still a solid chance that he ends up with a career as good as any of them.

Jason Heyward, OF, Braves (High-A Myrtle Beach)

With a surprisingly long stay in big-league camp, Heyward was one of the talks of spring training on the Florida side of things, so some were a bit surprised to see him start the year 3-for-17 in his first four games. Small sample sizes folks; the 2007 first-round pick went 2-for-3 on Sunday with a home run, and with four multi-hit games in his last six contests, including three homers, his averages are now at a very healthy .325/.438/.650. Keep in mind that Heyward hit just one home run in his first 22 games last season. He already has three this year, and eight of his 11 games have been home games at BB&T Coastal Field, where fly balls go to die. Ready to call it a breakout? Again, small sample sizes, but the results are encouraging.

Marcus Lemon, SS/2B, Rangers (Double-A Frisco)

Despite signing for $1 million out of the 2006 draft, Lemon has ended up buried in a loaded Rangers system. He’s not especially toolsy, but Chet’s kid is solid across the board and knows how to play fundamentally sound baseball, consistently reaching base at a healthy clip, and entering the year with career averages of .281/.367/.399. On Sunday, Frisco DH’d him just to keep his hot bat in the lineup, and though a 1-for-5 showing snapped his multi-hit streak at four games, it extended his overall season-starting streak to nine contests, as he’s 18-for-33 (.545) with four doubles and a triple. His range isn’t spectacular, but he makes every play that he gets to, and while he’s not a superstar in the making, I’d certainly take a shot at him in any trade talks with the Rangers.

Jesus Montero, C/DH, Yankees (High-A Tampa)

Once again, the Yankees have two quality prospects sharing time behind the plate; Austin Romine, a very good catcher who can hit a little is splitting backstop duties with Montero, a massive offensive force who can kind of maybe catch a little if you squint your eyes and crook your neck funny. The first half of that equation was clearly on display this weekend, as Montero went 9-for-13, including three doubles and his second home run of the year on Sunday, bumping up his early-season triple-slash line to .395/.452/.658 after ten games. In just five games behind the plate, the opposition has run on him nine times and been safe seven, but the value here is in the bat, as Montero is not only one of the youngest prospects in the Florida State League, he’s also one of the best.

Mike Stanton, OF, Marlins (High-A Jupiter)

Stanton entered the 2009 season with some lofty expectations, but 39 home runs in your full-season debut as a 19-year-old can do that. The question was: how would it translate as he moved from the best home-run park in a hitter’s league to the heavy air and big parks of Florida? While nobody was panicking after he had gone seven games with only one extra-base hit, nonetheless, a collective sigh of relief came this weekend as Stanton homered on Friday, Saturday, and Sunday, including a game yesterday where he went 5-for-5 with a double and four RBI. Sure, he’s still striking out a lot, with 11 whiffs in 36 at-bats, but just like last year, there’s so much production here that it almost doesn’t matter.

Angel Villalona, 1B, Giants (High-A San Jose)

Last year, Montero and Villalona were the subject of one of the more enjoyable debates of the season, and the subject of many conversations involved which extremely young Latin American was the better prospect in the Sally League. This year, they’ve been separated by geography, but one gets the feeling that the debate is hardly over; Villalona has kept pace with Montero, delivering two hits on both Friday and Sunday to give him seven multi-hit efforts and a .395/.385/.658 line after ten games in the California League. Have we mentioned that he doesn’t turn 19 until August? Some were concerned about last year’s .262/.312/.435 line, but they neglected to take into account that he was younger than most high school seniors at the time. Like Montero, this is a special hitter who both deserves significant patience, and who may come quickly enough that he doesn’t need it.

Josh Vitters, 3B, Cubs (Low-A Peroria)

On a prospect level, he’s almost all that the Cubs have, so there is a lot riding on Vitters’ young shoulders. While rain washed out his Friday contest, the Cubs are hoping that won’t slow down a roll that has seen their 2007 first-round pick go 9-for-16 in his last four games to raise his batting average to .423. That Vitters is hitting .423 in a seven-game stretch shouldn’t really surprise anyone; his plate coverage, swing mechanics, and bat speed are all among the best you’ll find in the minors. The only question is how many secondary skills he’ll be able to develop, since his plate coverage gives him so many hittable balls that there’s no real incentive for him to work on either his plate discipline or the lack of uppercut in his swing. So far? Zero home runs and zero walks in 26 at-bats; a tiny sample to be sure, but worth noting.

Alex White, RHP, University of North Carolina

In a draft with this much uncertainty, guys can move up with that one game against top competition in which they perform exceedingly well in front of a good number of scouts. That was certainly the case for White, who fired a 121-pitch one-hitter against Miami (Bryan Smith‘s #11 team) on Friday night. He has been consistently good all year; not eye-popping in a Strasburg-esque way, but in 63 innings he’s allowed just 49 hits, walked 23, and struck out 72. Scouts love his power frame and low- to mid-90s heat, but his secondary stuff is of some concern, as one scout characterized the Tar Heel as “a fastball-splitter guy-the kind of combination that worries me a bit.” Still, in the 2009 draft, beggars can’t be choosers, and White is on track to be a top five pick in June.