Brandon Allen, 1B, White Sox (Double-A Birmingham)

Ranked 99th on my Top 100 list coming into the year, Allen had a breakout campaign in 2008 with 29 home runs in 472 at-bats, but he still had four previous years of not-so-impressive performances to overcome to convince a significant number of doubters. With home runs on Saturday and Sunday, and 13 RBI in his last 11 games, Allen now has a nice track record of production at the upper levels with a .300/.369/.521 line, and scouts who have seen him this year have come away impressed.

Jake Arrieta, RHP, Orioles (Double-A Bowie)

Arrieta is somewhere in the middle when you look at Baltimore’s talented totem pole of top throwers (and that alliteration just won me a bet). He hasn’t gotten much attention this year, but it’s not because he’s been bad; he’s merely been good, without that one start worthy of a mention in Ten Pack or Minor League Update. That all changed on Saturday night, thanks to a seven-inning one-hit shutout that included a season-high 10 strikeouts. With a 2.70 ERA and 42 whiffs in 33 1/3 innings, Arrieta is on track to become one of the many arms that fixes Baltimore’s long-term pitching woes.

Peter Bourjos, CF, Angels (Double-A Arkansas)

When you think about the son of a scout, you imagine one of those gritty, grinder types who gets the most out of limited tools. But that’s not Bourjos, who is instead a player with a classic leadoff man’s package, one that includes a line-drive bat, 70 speed on the 20-80 scouting scale, and the ability to make use of it with outstanding center-field play and basestealing. His only problem was a free-swinging style that led to just 19 walks all of last year. Six hits in two games over the weekend has now extended his hitting streak to ten games (during which he’s gone 16-for-40), and, more importantly, he’s already worked 13 free passes in 129 at-bats.

Michael Bowden, RHP, Red Sox (Triple-A Pawtucket)

Bowden and Clay Buchholz currently make up one of, if not the best one-two pitching single-team rotation punches anywhere in the minors. Bowden kept up his end of the bargain on Sunday, needing just 93 pitches to twirl eight shutout innings while allowing three hits, walking four, and striking out seven. In his seven starts for the PawSox this year, Bowden has allowed zero earned runs on four different occasions, one run twice, and two runs once-thus the ridiculous 0.86 ERA. While his 28:16 ratio of strikeouts to walks in 42 innings isn’t especially eye-popping, but the 19 hits allowed and .136 opponents average certainly are.

Madison Bumgarner, LHP, Giants (Double-A Connecticut)

Tim Alderson announced his Eastern League arrival with authority by throwing six no-hit innings in his Double-A debut, and Bumgarner followed with an outing that was merely very good, as he gave up one run over six innings on seven hits. Sunday afternoon, however, he made up for it with six one-hit innings and nine strikeouts. Whenever I would write about the Giants having the most terrifying rotation in the game, I usually attached the arrival year of 2011 to it; that may prove to be too conservative an estimate.

Kila Ka’aihue
, 1B, Royals (Triple-A Omaha)

After leading the minors in on-base percentage last year while finishing second in slugging, Ka’aihue’s slow start had many wondering if his 2008 season was just some kind of mirage, with the Royals’ strange acquisition of Mike Jacobs adding to the feeling that maybe there’s something here that we just don’t get. So much for that. With home runs on Friday and Sunday as part of a five-game surge that has seen him go 10-for-20 with three doubles, four home runs, and five walks, the big Hawaiian is suddenly batting .270/.439/.548 overall, and everything seems normal again.

Alex Liddi, 3B, Mariners (High-A High Desert)

The Mariners have a long-standing reputation for having one of the most wide-reaching international scouting departments out there, so it wasn’t much of a surprise when they spent six figures in 2005 to sign Liddi out of Italy. It’s easy to see what they liked about him, as he’s 6-foot-4 with long limbs and broad shoulders, but baseball hasn’t come so quickly for him, as he did little in two Midwest League seasons, hitting .240 with eight home runs in 2007, and showing no progress last year with a .244 batting average and just six bombs. High Desert does wonders for any hitter, but it’s hard not to think some progress has been made here as well, as home runs on Saturday and Sunday gave Liddi 10 already on this young season, to go with an attention-generating overall line of .361/.395/.674.

David Price, LHP, Rays (Triple-A Durham)

Two of the most frequently repeated questions overheard early this season in the minors involve what is ‘wrong’ with Matt Wieters and David Price, the top two prospects in the game. The answer, of course, is nothing at all. Wieters homered on Friday and had a triple while scoring the only run of the game on Saturday, while Price put an exclamation point on the weekend Sunday afternoon with five no-hit innings, walking two and striking out nine. The Rays’ experiment with very strict pitch counts at Triple-A (Price was lifted after just 82 pitches, his highest total of the year), meant that he left well before he was tired, but at least the questions about the pair should be fading away soon.

Ben Revere, CF, Twins (High-A Fort Myers)

After flirting with .400 in his full-season debut in ’08, the Twins’ top prospect came into the year with some massive expectations to fulfill. Without much in the way of power or patience, Revere is the kind of player who needs to hit .320 to be of value, and the scary thing is that he shows no indications that he’s not capable of that. With three multi-hit games over the weekend (and four in a row overall), plus a current 10-game hitting streak in which he’s gone 20-for-41, Revere is now batting .346/.412/.406. He’s also hitting with improved plate discipline, drawing 14 walks, while making even better contact (just eight strikeouts in 133 at-bats) than he showed last year.

Josh Vitters, 3B, Cubs (Single-A Peoria)

It’s not easy being the only premium prospect in the system, but with three hits each game on Friday, Saturday, and Sunday, Vitters is hitting .407 in 16 games this year, and the power is beginning to show up in a major way, as the 2007 first-rounder hit his fourth home run of the year on Friday, and added a pair of doubles and his fifth homer on Sunday. Early on, scouts were calling Brett Lawrie the best young hitter in the Midwest League, but a few trips to Peoria have changed that assessment, and Vitters now holds the title.