SoxProspects.com: Revisiting the top 5

Red Sox top prospects (left-right) Casey Kelly, Lars Anderson and Jose Iglesias are living up to expectations so far this season. Getty Images

Now that we’re more than six weeks into the minor league season, here’s an updated look at the top five prospects in the Red Sox system. While all five have had some ups and downs early on, each has made significant individual strides and all look like potential major league regulars at this point.

The rankings have remained fairly steady since the beginning of the season, except for a diminution in the prospect status of Josh Reddick. The 23-year-old outfielder has disappointed in 2010, hitting .187/.220/.355 with Triple-A Pawtucket, making him one of the least-productive regulars in the International League this season and dropping him out of top-tier prospect status.

With that, here is the updated top five:

1. Casey Kelly, RHP

Age: 20 years, 7 months

How Acquired: Drafted in the 1st round, 2008

Assignment: Double-A Portland (League average age for pitchers: 24.3)

Line: 0-3, 4.45 ERA, 28 strikeouts, 13 walks, 28.1 IP

The Report: The Sox challenged Kelly with an aggressive placement in Double-A this spring, making him the youngest pitcher in the Eastern League. The right-hander has shown flashes of dominance in his first eight outings, but has also had a few bad starts where he struggled to find his control. Focused solely on pitching for the first time in his career, the 20-year-old has been on a limited pitch count early in the season so that he doesn’t jump too much beyond his 2009 innings total. Having pitched roughly 120 innings in 2009 (including spring training), look for Kelly to be limited to about 160 innings in 2010. Coming into the season, two primary emphasis points for Kelly were: (1) picking up a few ticks of velocity on his fastball while maintaining movement and control; and (2) missing more bats. On the first point, his fastball has generally registered around 90-92 mph early in 2010, about the same velocity that he had in 2009, but there have been reports that he has topped out at 94 mph on occasion. At the same time, he has had bouts where his fastball has been flat, leading to lackluster command and subpar results. In regards to the second point, Kelly has increased his strikeout-per-nine-inning figure from 7.01 in 2009 to 8.89 in 2010 -- a solid improvement in a key area. As far as when Kelly can be expected to land in Boston, look for a possible cup-of-coffee in September, an assignment to Pawtucket out of the gate in 2011, and an early-to-mid-season promotion to Boston next season.

2. Lars Anderson, 1B

Age: 22 years, 8 months

How Acquired: Drafted in the 18th round, 2006

Assignment: Triple-A Pawtucket (League average age for hitters: 27.0)

Line: .302/.387/.550, 7 HR, 129 AB (combined Portland/Pawtucket stats)

The Report: After showing signs of the Lars Anderson of old throughout minor league spring training, reports were that the Red Sox front office contemplated promoting the first baseman to Pawtucket to start the 2010 season. They opted to send him back to Portland, where he dominated through 17 games, leading the Eastern League with a .677 slugging percentage prior to his April 29 promotion to Pawtucket. While his stat line hasn’t been as impressive in his first 20 games with Pawtucket (.254/.367/.433), he looks quite comfortable at the plate and should shortly make the necessary adjustments required to succeed at that level. That being said, Anderson could certainly stand to be more aggressive at the plate. The 22-year-old tends to take a lot of strikes waiting for the right pitch -- which results in both a lot of walks and a fair share of strikeouts -- and that could frustrate some Boston fans when he gets the call to the majors. Don’t be surprised if that call-up occurs prior to Sept. 1 this year, but that may depend on Boston’s status in the playoff hunt and whether there is a spot for the first baseman to get everyday at-bats.

3. Ryan Kalish, OF

Age: 22 years, 2 months

How Acquired: Drafted in the 9th round, 2006

Assignment: Double-A Portland (League average age for hitters: 24.3)

Line: .254/.376/.440, 6 HR, 134 AB

The Report: Don’t let Kalish’s mediocre batting average fool you -- he has been quite impressive at the plate this season, showing increased power, excellent plate discipline, and hard contact rates. His peripherals indicate that his low batting average is a matter of bad luck to this point, something that should regress back to the norm over the course of the season. Additionally, Kalish has shown impressive base-running skills and solid all-around defensive tools, playing all three outfield positions more than adequately. As a regular, he looks best suited for left field from a defensive standpoint at this stage, as his arm is not that of an ideal everyday right fielder and his range is not that of an ideal everyday center fielder. Ultimately, Kalish projects to be a .285/.385/.425, 20 home run, 25 stolen base type of player at the major league level. The question of his long-term status with the Sox may be one of whether the team can move forward with that type of power production in left field, where the expectations include higher home run and slugging totals.

4. Anthony Rizzo, 1B

Age: 20 years, 9 months

How Acquired: Drafted in the 6th round, 2007

Assignment: Double-A Portland (League average age for hitters: 24.3)

Line: .258/.341/.478, 7 HR, 159 AB (combined Salem/Portland stats)

The Report: As many fans know, Rizzo missed most of the 2008 season with Hodgkin's Lymphoma after coming out of the gates with a .372/.402/.556 line with Low-A Greenville at the age of 18. Despite missing that full season, Rizzo is still well ahead of the curve in terms of age advancement, particularly since being promoted to Portland on May 10. He shows an advanced approach at the plate, a good eye, and a quick bat. His power, which has always involved a lot of projection, is developing nicely in 2010 to the tune of 7 home runs in 159 at-bats. He could develop into a 35-home-run hitter over the long term. Rizzo is also an excellent defender at first base with a solid arm, surprising lateral quickness for his size, and outstanding fundamentals. He’ll be a fan favorite when he gets to Fenway Park, but don’t expect that to be until 2012. Until then, Rizzo will need to get adjusted to advanced pitching, cut down on the strikeouts, and continue to put work in toward building more muscle onto his broad frame.

5. Jose Iglesias, SS

Age: 20 years, 4 months

How Acquired: International free agent, 2009

Assignment: Double-A Portland (League average age for hitters: 24.3)

Line: .301/.333/.406, 0 HR, 133 AB

The Report: The Cuban shortstop has come as-advertised on defense, demonstrating outstanding instincts, extremely quick hands and excellent fluidity. Simply put, his glove is major league ready right now. Meanwhile, Iglesias’ offense has been a pleasant surprise. His smooth mechanics and quick bat have resulted in a lot of contact, evidenced by a .301 batting average. However, he still needs some work with plate discipline, as he doesn’t like to take a lot of pitches and tends to fish for balls outside of the zone a la Nomar Garciaparra. He also hasn’t flashed a lot of power, with no home runs and just 8 doubles to this point. All that being said, Iglesias is still four years younger than the average competition in the Eastern League, and those are tools that can certainly develop in time. Look for Iglesias to spend the remainder of the minor league season in Portland while working on those aspects of his game, with the possibility of a limited call-up in September. Like Kelly, the shortstop is likely to begin the 2011 season in Pawtucket in the hopes of making major league contributions by mid-season next year.

Mike Andrews is designer and developer of SoxProspects.com and a special contributor to ESPNBoston.com.