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Rasmus: Red Bird Building Block

The 2009 post-season surely ended on a sour note for the St. Louis Cardinals, swept in the NLDS by the Los Angeles Dodgers.

On a happier note, the Cardinals boast an enviable collection of top-shelf talent. There’s that Pujols fellow, of course. But Yadier Molina‘s decent bat for the catcher position led a 3.4 WAR season. SS Brendan Ryan might not cause opposing pitchers to lose much sleep, but his slick glove work led to a 3.2 WAR campaign (does anyone else think that he looks like Super Mario with that red cap and bushy mustache?) On the bump, Adam Wainwright (5.7 WAR) and Chris Carpenter (5.6 WAR) form a one-two punch few can match.

Though he’s still rough around the edges, CF Colby Rasmus has the talent to join that group. Playing most of the year as a 22 year-old, the rangy rookie compiled 2.3 WAR.

The 28th overall selection in the 2005 amateur draft, Rasmus was part of an absurdly deep class of prep outfielders that year. Other first-round fly catchers from 2005 include Justin Upton, Cameron Maybin, Andrew McCutchen and Jay Bruce.

Rasmus raced through the system, reaching the AA Texas League by age 20 in 2007. The 6-2 lefty hit plenty of homers for Springfield, belting 29 big-flys and posting a monstrous .275/.381/.551 line in 556 PA. Colby showed off his broad skill set, working the count (12.9 BB%), hitting for power (.275 ISO), swiping bags efficiently (18 SB, 3 CS) and earning rave reviews for his work in center field.

In its 2008 Prospect Handbook, Baseball America named Rasmus as a consensus top-10 prospect. Praising Rasmus’ “smooth, balanced swing that packs plenty of punch”, BA claimed he had the “head-turning ability of a potential big league all-star.”

Colby entered the 2008 season with considerable fanfare, but he stumbled for the first time in his career at AAA Memphis. Rasmus got off to a sluggish start at the plate, and just when he was starting to make pitchers pay, he sprained his left knee in July on a check swing.

Overall, St. Louis’ prized prospect batted .251/.346/.396 in 387 PA. Rasmus remained disciplined, drawing a walk in 12.9% of his PA again, while still punching out a little more than 20 percent of the time. His extra-base pop suffered, however, with a .145 ISO. Colby stayed smart on the base paths, with 15 SB in 18 attempts. Baseball America remained a big fan, saying Rasmus “should be the first impact position player signed and developed by St. Louis since Albert Pujols.”

In 2009, Rasmus played his way into an everyday role with the N.L. Central Division champs. He hit .251/.307/.407 in 520 PA. Colby popped 16 homers with a .156 ISO, while playing an outstanding center field (+10.9 UZR/150).

Rasmus wasn’t especially patient at the plate, drawing walks at a 7.1 percent clip while whiffing an even 20 percent. Not bashful in terms of taking a cut at a pitch within the strike zone, Colby posted a 73.5 Z-Swing% (65.9% MLB average). That was one of the 20 highest rates among qualified batters. But, he wasn’t some unrestrained hacker, either, as he swung at 25.9 percent of pitches outside of the strike zone (slightly above the 25.1% MLB average).

Colby’s biggest problem during his rookie year was those pesky southpaw pitchers. Fellow left-handers owned him to the tune of a .160/.219/.255 triple-slash in 115 PA.

Baseball-Reference offers a helpful stat called sOPS+, which compares a player’s performance in a given split to the league average. a 100 sOPS+ means the player was average in the split category. A figure above 100 indicates he was better than the league average, while a number under 100 indicates a below-average performance. Rasmus’ sOPS+ versus LHP was 35.

Of course, we’re dealing with an awfully small sample of PA against lefties. No bold conclusions should be taken from one year’s worth of platoon splits. Rasmus generally held his own against lefties in the minors, with a career .275/.371/.455 line vs. LHP.

Perhaps the most peculiar aspect of Colby’s rookie season was his stealing just three bases all year long. Though he never racked up massive SB totals, Rasmus holds a career 81.3 percent success rate in the minors. And, according to Baseball Prospectus’ Equivalent Base Runs stat (definition here), Rasmus was the top base runner on the team and one of the 20 best in the majors. Let ’em loose, guys!

Rasmus has some kinks to work out in terms of working the count and hanging tough against lefty pitching, but he has the tools to become one of the most valuable properties in the game. Those in keeper leagues should have a white-knuckle grip on this guy, and he’s a strong breakout candidate for 2010.