Phillies Prospect Roundup: Read our Commenters' Firsthand Reports!

Two items to kick off this week's roundup. First, if you haven't had the chance, please check out the Fanposts that Romero and The Dark have written recently on their trips to see the BlueClaws and Threshers, respectively. Pieces like this are always appreciated, as in season scouting reports are often difficult to come by, and the numbers can only tell us so much.

The second item follows from a change that Fangraphs made to their hitter statistics last week: changing K% to calculate strikeouts as a percentage of plate appearances instead of at bats. This makes K% and BB% consistent with each other, and as David Appelman notes, it's not a change that drastically alters the numbers to the point where our frame of reference changes.  I've gone ahead and updated the site Prospect Primer to reflect the change.

With that said, let's get on with the show. Check below the jump for updates on some of the organization's athletic young outfielders (of course), a pair of older, bat first prospects, and a Canadian right-hander who tossed a gem of a game on Saturday.

Trevor May, RHP, Clearwater: The issue with the big right-hander has always been his control, as his power arsenal has always generated swings and misses (as his career 11.6 K/9 attests). While the big righty hasn't definitively solved the issue by any stretch, he's certainly been pounding the strike zone lately, with just 4 walks (against 25 strikeouts) in 18.0 innings over his last 3 starts, including a 7-inning complete game shutout Saturday a week ago. I don't think he has quite the same upside as teammates Jarred Cosart and Brody Colvin, but he's having the best season of the three, and it's not particularly close.

Jiwan James, OF-S, Clearwater: As loyal TGP commenter philsandthrills pointed out on Twitter, James has been on a tear recently, going .323/.432/.398 since the All-Star break to bring his season line to .277/.341/.384. Most encouraging to me has been his control of the strike zone as of late, as he's walked 9 times to just 11 strikeouts in the month of July. James is 22 now, and while we're still waiting and hoping for the big breakout, he's putting up better numbers in High A this year than he put up in Low A last year, so at the very least, he's holding serve.

Aaron Altherr, OF-R, Williamsport: Altherr had a pretty brutal 41-game stretch in Lakewood this year, hitting .211/.272/.272 with 6.7% BB and 28.8% K, but he's been much better since heading to Williamsport, hitting .288/.318/.433, swiping 10 bases in 11 tries, and serving as the subject of some good scouting reports. He's still very raw, and he's only walked 4 times in 112 plate appearances (3.6% BB), but he's young, his tools are excellent, and he's showing some ability to convert those tools into actual baseball skills, which is all you can ask from a high school toolshed draft pick.

Colin Kleven, RHP, Williamsport: From that same Phuture Phillies piece, Kleven has been clocked as high as 95 on the gun, which in and of itself makes him a name to watch. Performances like Saturday's only add to the intrigue, as Kleven threw 7 scoreless innings, allowed just 3 hits and 0 walks, struck out 2, and got 15 ground ball outs. The club's 33rd round pick back in 2009 out of a high school in British Columbia, Kleven is a projectable right-hander who has specialized in getting ground balls (61% on the year).  He's not racking up strikeouts (15 in 26.1 innings), but he's keeping the walks down (just 7 on the year) and is allowing just a .304 slugging percentage, which is a nice skill set.

Zach Collier, OF-L, Lakewood: It's easy to forget that Collier is still just 20 years old, seeing as it's his third full season in pro ball (including 2010, which he sat out of with an injury). His .267/.343/.378 line isn't earth shattering by any means, but there are several reasons to be encouraged.  He's controlled the strike zone well (9.4% BB and 20.5% K), stolen 25 bases at a 71.4% clip, and flashed a good arm in the outfield (6 outfield assists). It's not a huge breakout season by any means, but it's the most success Collier has had since his time with the GCL Phillies in 2008, so it qualifies as a successful campaign thus far.

J.C. Ramirez, RHP, Reading: The aforementioned Prospect Primer discusses the importance of Double-A as the biggest testing ground for prospects, and I think that may explain what's happened to the Nicaraguan right-hander in 2011. He had some superficial success early on, but the poor peripherals -- 4.8 K/9, 3.1 BB/9, 0.75 HR/9, 40% GB, 4.35 FIP -- have started to catch up with him, with Thursday's outing (3.2 IP, 9 H, 7 R, 2 BB, 3 K) serving as a regression-in-action sort of situation. Until Ramirez starts missing more bats, there's definite reason for concern here.

Cody Overbeck, 1B-R, Lehigh Valley: Overbeck certainly earned his promotion to Triple-A after his .275/.331/.532 showing in 62 games in Reading, but it's been tougher sledding since heading up Route 222. In 29 games, Overbeck has managed just a .236/.296/.404 line, and the culprit is his plate discipline: he's walked just 4.9% of the time while striking out in 35.3% of his plate appearances. He did have a bit more success in the past week, going 5-for-15 with a homer and a double, but until he either cuts down on the holes in his swing or develops a more patient approach, he'll be too easy for pitchers to exploit.

Matt Rizzotti, 1B-L, Reading: I often think about Rizzotti and Overbeck together, because while Overbeck is six months younger and offers a bit more with the leather, they're both older, bat only prospects, and the truth of the matter is that I believe in Rizzotti's bat more. He's got a cumulative .323/.412/.572 line at the Double-A level (including a .295/.384/.521 performance this year), but unlike Overbeck, he's always controlled the strike zone pretty well, with a 12.6% BB and a 20.7% K in his time in Reading. He's 25 and by all accounts pretty brutal defensively, but he's a good enough hitter that he deserves a shot to prove himself in Triple-A, whether with the Phillies or another organization.

Lendy Castillo, RHP, Lakewood: In that Fanpost from Romero linked above, he mentioned Castillo's velocity (94 to 96), which makes him an interesting arm to monitor. He put up good numbers for the GCL Phillies last year (10.3 K/9, 3.6 BB/9, 0.40 HR/9, 2.98 FIP), albeit as a 21-year old, and has followed that up with a nice campaign for the BlueClaws, with 9.3 K/9, 2.1 BB/9, 0.00 HR/9, a 42% GB and a 2.33 FIP. He's a 22-year old reliever in Low A, so he's not exactly a mega-prospect, but easy plus velocity is a rare commodity, and gives Castillo back of the bullpen potential.

Francisco Diaz, C-S, Williamsport: I'll admit that I've always just kind of glanced over Diaz's name in the box scores, and in my defense, guys with a career OPS well below .700 aren't usually worth focusing on. That said, the more I look at Diaz, I admit to being a bit intrigued: since struggling as a 17-year old in the Venezuelan Summer League back in 2007, he's walked more than he's struck out (50 to 48 in 365 plate appearances), and is very good defensively (thanks to Mitch Rupert for this). The power clearly isn't there right now, but the walks mean his .206/.346/.233 line actually isn't that far below league average in the New York-Penn League.  Diaz is just 21, and catchers are often notoriously slow to develop due to the defensive demands of the position, so I'll be looking for his name in the box scores going forward.