Many analysts thought the Oakland Athletics traded away their chances for a successful 2005 this past off-season when they sent pitchers Tim Hudson and Mark Mulder to the National League, but they’ve surged back into the playoff hunt. They’ve done so largely on the backs of four outstanding Rookie of the Year candidates: right fielder Nick Swisher, first baseman/designated hitter Dan Johnson, starter Joe Blanton, and closer Huston Street.

Developing top-notch talent has long been an Oakland trademark. A roster composed of their recent homegrown studs would be the envy of any general manager: Jason Giambi, Miguel Tejada, Eric Chavez, and the ‘Big Three’ of Barry Zito, Hudson, and Mulder. More recently, the A’s had the 2004 AL Rookie of the Year in shortstop Bobby Crosby, and looking back further we remember that the A’s dominated the ROY contest from 1987 to 1989 with back-to-back-to-back wins by Jose Canseco, Mark McGwire, and Walt Weiss. This year’s crop of young talent rightly deserves to join that long list of outstanding young players.

Of the four mentioned above, Swisher, the 16th overall pick on the famous “Moneyball” draft of 2002, is least likely to win this year’s Rookie of the Year award. His batting line of .235 AVG/.317 OBA/.435 SLG may not turn many heads, but Swisher is currently on pace for 20 home runs and 74 RBI – numbers that only 12 players have matched in their rookie seasons over the past decade.

First baseman Dan Johnson was much less touted out of college in 2001. The slugging left-handed batter fell all the way to the seventh round due to his poor defense and the fact that he only started hitting impressively toward the end of his college career. Once drafted, Johnson absolutely crushed the ball at every minor league stop, and didn’t stop when an elbow injury to designated hitter Erubiel Durazo gave Johnson a shot on the major league squad in late May. After just 227 plate appearances, Johnson was hitting 321/.405/.546.Since then, he’s leveled off at a steady .292/.370/.475 with 30 extra base hits in 85 games.

Concerns over his defense at first base are quickly waning and there is little doubt that he can handle himself as a starting 1B/DH on a contending AL squad. Oakland isn’t afraid of players who are flawed in some way, and Johnson perfectly fits that model with his lack of speed and a record of spotty defense. He more than makes up for those shortcomings with his offense, though. With Durazo heading towards free agency and Scott Hatteberg’s 2006 option coming in at a pricey $2,800,000, it seems almost certain that Johnson’s position on the squad is secure for next year.

The outstanding contributions from 2005 Athletics’ rookies have also come on the pitching side of the ledger, particularly from starter Joe Blanton and reliever Huston Street. Blanton was another member of the famed “Moneyball” draft, going 24th overall. Thus far, he has started 28 games with a 3.61 ERA in 169 innings.

Instead of having just one or two pitches that blow hitters away, Blanton succeeds with four average-to-slightly above average pitches that he sets up and locates well. Scouts may not be blown away with the raw materials, but his performance shows that his arsenal is enough to succeed.

Blanton’s 2.20 ERA since the All-Star break has been a big part of the A’s 33-19 record during that period. The young righty is on pace to start 32 games, pitch 194 innings, strikeout 116 hitters, and finish with an ERA under 3.60. That should easily add up to quite a few Rookie of the Year votes.

Reliever Huston Street is another first-round talent. The hard-throwing Texan was taken 40th overall in the 2004 draft, after which he quickly swept through three minor league levels and finished the year at Triple-A Sacramento with a combined ERA of 1.38 in 26 innings with 30 strikeouts and only eight walks.

Unsurprisingly, those filthy minor league numbers led the A’s to quickly promote Street to the majors, where he has been nothing short of amazing. In just 67.2 major league innings, Street has compiled a 1.20 ERA with 65 strikeouts.

Street took over as the team’s closer shortly after Octavio Dotel hit the disabled list with an elbow injury and his season has been historical: By the end of the year, he should be only the fourth rookie since 1920 to go over 70 innings pitched with a sub-1.50 ERA.

Street’s fastball isn’t dominating in terms of velocity, but it has heavy, bat breaking sink. His hard slider offsets the fastball perfectly due to its sharp breaking action but, as his 13 walks allowed suggest, his most exemplary quality is his impeccable control. All in all, Street’s outstanding season makes him an early Rookie of the Year favorite.

According to VORP (Value Over Replacement Player, Baseball Prospectus’s measure of how many more runs a player is worth than a typical Triple-A veteran or bench player in the same amount of playing time),these four rookies have accounted for 24% of the total offensive and pitching contributions from all Oakland Athletics this season. Being able to depend on that level of output from their farm system year in and year out explains why the A’s have been so consistent over the past seven years, and certainly suggests they’ll remain a perennial threat in the AL West for years to come.

Mr. Gorman writes for Baseball Prospectus.For more state-of-the-art commentary, visit baseballprospectus.com.