Worst defender at each position?

Well this is according to Fangraphs.com, using the UZR statistic. UZR stands for ultimate zone rating and is what many major league GM's use to measure a player's defense ability.

Catcher- Rod Barajas, Toronto Blue Jays. They don't use this statistic for catcher, but he has made the most amount of errors out of all catchers in the major leagues this year.

Shortstop- Yuniesky Betancourt, Seattle Mariners (UZR rating of -8.5)

Second Base- Dan Uggla, Florida Marlins (UZR rating of -7.9)

Center Field- Vernon Wells, Toronto Blue Jays (UZR rating of -20.3)

Third Base- Michael Young, Texas Rangers (UZR rating of -10.5)

Right Field- Jose Guillen, Kansas City Royals (UZR rating of -14.3)

Left Field- Jason Bay, Boston Red Sox (UZR rating of -7.0)

First Base- Nick Johnson, Washington Nationals (UZR rating of -6.9)

To give you an idea of what a good UZR is, Nyjer Morgan of the Pittsburgh Pirates has the best rating at 12.4

salty
lugo
teriot does he play2nd
wiggington when he plays outfield
wiggington
wiggington
wiggington
nick johnson

bengie molina
julio lugo
robinson cano
melky cabera
mike lowell
jermaine dye

dimitri young

Catcher- AJ Pierzynski CWS (4 errors this season and has allowed 49 SB in 54 attempts)
First Base- Nick Johnson WAS (7 errors which is tied with Carlos Pena for the most, but Pena won a Gold Glove last year so I gave it to Johnson)
Second Base- Jose Lopez SEA (9 errors this season in the 6th least amount of chances)
Third Base- Chipper Jones ATL (13 errors this season and a .899 FPCT, odd for a normally solid 3B)
Shortstop- Yunel Escobar ATL (11 errors this season and still very immature)
Left Field- Alfonso Soriano CHC (7 errors this season and even though he's a converted IF, that is very poor defending)
Center Field- Willy Taveras CIN (3 errors which is second most by CF and he has a mediocre to weak arm)
Right Field- Justin Upton ARI (6 errors this season as a RF)

Center field.