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Ian Kinsler and Placido Polando are big reasons while their teams are doing so well defensively.

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It's no surprise that the Boston Red Sox are leading the American League East. What may come as a surprise are the other division leaders in the AL: The Detroit Tigers and the Texas Rangers. For some both were some what of sleepers in their respective divisions, but I think most figured the Los Angeles Angels and the Cleveland Indians would top their divisions. While the Angels are just a game behind Texas, the Indians are in the Central's cellar, and at 10 games out they could become sellers on the trade market very shortly.

Both the Rangers and Tigers are in the upper to middle pack in terms of runs scored in the American League, however, their biggest improvements have come on the defensive side. Following the blueprint of the 2008 AL Champion Rays' both teams improved their defensives this offseason which in turn has improved their pitching staffs.

Like the Rays, the Tigers acquired a slick fielding short stop from the Minnesota Twins to help solidify their defense. For the Rays it was Jason Bartlett, for the Tigers it has been Adam Everett. In 2008, Edgar Renteria manned the short stop position and was below average with a -0.9 UZR. That's not terrible, but so far Adam Everett has a 2.7 UZR at the same position.

Handing Brandon Inge the full time job at third base is looking like a great decision. After posting well above average UZR's in 2006 and 2007 at the hot corner, the Tigers moved Inge around in 2008; that experiment failed. Now, entrenched at third this season, Inge has posted the second highest UZR (8.9) at third base in the majors.

Placido Polanco has also been stellar defensively. He leads the majors in UZR at second base (8.9) and has shown the best range by far of anybody else at the keystone position. Having two above average centerfielders playing side by side in Curtis Granderson and Josh Anderson helps in the outfield especially since Magglio Ordonez, when he was playing, was below average in right field. He has been since replaced by Clete Thomas, who has shown to be above average in right field, albeit a small sample size.

The Tigers have improved from 26^th in team UZR in 2008 to 1^st in 2009. This has helped drop the teams ERA from 4.91 to 4.24. Their starters especially have benefitted seeing an ERA drop of nearly a run year over year. The Tigers starters themselves have also improved dropping a little over a half of a run of their FIP.

For the Rangers the defensive turnaround has also been significant. The Rangers had the worst team UZR in 2008. They finished with a combined -51.7. For comparisons sake, the absolutely awful 2007 Tampa Bay Rays finished with a -57.7. As of Sunday's UZR update, the Rangers sit 3^rd in the AL right behind the Tigers and the Rays.

The biggest change for the Rangers, not surprisingly, has come at the short stop position. In a move that ruffled a few feathers, the team moved "gold glove" short stop Michael Young, who finished with a -5.8 UZR at the position in 2008, to third base in favor of prospect Elvis Andrus. All Andrus has done is put up a 6.7 UZR at the position; the best in the league. Meanwhile Young continues to struggle defensively and his -9.8 UZR is the worst of any third basemen in baseball.

Despite Young's defense, the Rangers have improved in other positions. Nelson Cruz figured to replace Milton Bradley's bat in the lineup, but nobody expected him to excel defensively. With an 11.6 in right field, Cruz has the highest UZR among position players...period. Texas is also enjoying a fine defensive season from Ian Kinsler, who is posting a positive (6.0) UZR for the first time in his career at second base.

The impact of the Rangers defense on their pitching staff is even more evident than that of the Tigers. Overall, the Rangers have enjoyed a 0.99 drop in team ERA. The impact has been felt even more in the rotation where the drop is a 1.22. However, the rotation's FIP has dropped just 0.16 from year to year. The big drop has been in BABIP. In 2008, the Rangers rotation had a combined BABIP of .327. That number has dropped to .282 this year.

The old adage is pitching wins championships, but as the Rays learned in 2008, and the Rangers and Tigers are seeing in 2009, sometimes defense makes that pitching.

Just a quick note; UZR is a great tool to measure how a team or player has done defensively, but it holds little predictive value going forward.