We all know Kenny Williams loves to trade prospects for proven major leaguers, going for stability over upside. This is a look at one of those trades and to see if Kenny did the right thing.

It was a dark and hot stormy summer night on July 7th, 2009. The White Sox were floundering in third place at 42-40 behind the 43-40 Twins and the 44-48 Tigers. Looking at the tired and beaten scrappers, General Manager Kenny Williams knew he had to plan something, attack some overlooked two meter weakness in the enemy’s defense.

via blog.al.com

So as I was just settling into my seat on the one hundred level only ten rows behind first base, I look up to the scoreboard and see that White Sox first baseman prospect Brandon Allen, in a yearly ritual of trades to the Arizona Diamondbacks required to appease the baseball gods, was traded for failed closer Tony Pena. At the time, I was a few months wise to SSS, and was hooked to larry’s minor league updates and the fantastic Birmingham Barons season, due to no little part from Brandon Allen himself. Instead of relaxing with a hot dog while cheering the Sox onto first place, I slumped down in my seat in disbelief. Thankfully, Paul Konerko got the news that his competition was eliminated and celebrated the night with a three home run game, including a grand slam that sealed the 10-6 win and made me a happy camper for the night.

More after the jump.

What he was with us: Brandon Allen was ranked fifth in larrys White Sox minor league prospects ranking at his time of trade. His memorable moments include being drafted in the fifth round of the 2004 Major League Baseball Draft at age 19 out of high school. A huge project, Allen struggled mightily in the low As. It was not until 2008 when he broke out and earned a late promotion to AA. Throughout 2008 and 2009, he consistently improved upon his strikeout/walk ratio while continuing to show tremendous power potential. His highlights before being traded were hitting two home runs off David Price, and being promoted to AAA in late 2009, putting him on track to be considered a solid replacement for Konerko/Thome in 2010.

His minor league stat line in AA in 2009: .290, .372, .452. Walks hung around 11% while strikeouts improved to 19.5% from 26% in 2008.

Scouting report: Showed good power in a park that suppressed it. Had good base stealing speed for a first baseman and was mentioned as an option for the outfield. Solid defensively at first. Needed to improve walk/strikeout ratio, which he did.

Where he is right now: After hitting .261, .405, .528 in AAA Reno, Allen was called up to the majors for the first time on August 22, 2009 and made his debut that day for the Diamondbacks. He went 1-4 with a single. Allen would play in 32 games that season and finished with a .202, .284, .385 line.

After spending most of the 2010 season at AAA Reno again, Allen received a September call up. In his first game up, he hit his first career grand slam against the San Diego Padres. He finished the season with a .267, .393, .400 line in 22 games. Most surprising is that he played most of his games in left field, with 14 starts there, compared to 2 starts at first base. 

Allens grand slam and outfield catch: http://mlb.mlb.com/video/play.jsp?content_id=11625335

Where he might have been: I had hoped he could replace Thome in 2010, providing a young cheap speed/power combo from the left side. As it is, it looks like he will start for the Diamondbacks in left field on opening day, where believe it or not, his fielding has above average. Fangraphs (which doesn't exist), ranked his defense at 2.6 runs prevented (SSS warning, I dont buy his defense in the outfield. It may be passable).  Quite frankly, I think this trade will sting next season if he can keep close to the numbers he had in 2010, and the fact that he is still pre-arb makes this hurt all the more.

Bill James prediction for 2011: .251, .338, .462 with a 11% walk rate, 25% strike out rate, and 24 home runs in 143 games.