Members of the Houston Fire Department's honor guard perform in tribute of the terrorist attacks of Sept. 11, 2001, before a baseball game between the Houston Astros and the Chicago Cubs, Tuesday, Sept. 11, 2012, in Houston. (AP Photo/Pat Sullivan)

Chicago Cubs' Justin Germano delivers a pitch against the Houston Astros in the first inning of a baseball game, Tuesday, Sept. 11, 2012, in Houston. (AP Photo/Pat Sullivan)

Houston Astros' Jordan Lyles delivers a pitch against the Chicago Cubs in the second inning of a baseball game, Tuesday, Sept. 11, 2012, in Houston. (AP Photo/Pat Sullivan)

Houston Astros first baseman Brett Wallace (29) comes down on Chicago Cubs' Anthony Rizzo (44) after reaching high for the ball in the third inning of a baseball game, Tuesday, Sept. 11, 2012, in Houston. Rizzo went down and was helped from the field. (AP Photo/Pat Sullivan)

Houston Astros' Jordan Schafer (1) slides to second base as Chicago Cubs' Starlin Castro (13) readies to make the catch on a force out in the fifth inning of a baseball game, Tuesday, Sept. 11, 2012, in Houston. (AP Photo/Pat Sullivan)

Umpire Doug Eddings (88) explains his call on a Houston Astros' Justin Maxwell steal of second base to Chicago Cubs manager Dale Sveum, center, Luis Valbuena (24), Darwin Barney (15) and Starlin Castro (13) in the sixth inning of a baseball game, Tuesday, Sept. 11, 2012, in Houston. (AP Photo/Pat Sullivan)

El taponero nicaragüense Wilton López, de los Astros de Houston, celebra el último out, en el duelo contra los Cachorros de Chicago, el martes 11 de septiembre de 2012 (AP Foto/Pat Sullivan)

Houston Astros closer Wilton Lopez celebrates the final out as the Astros defeat the Chicago Cubs 1-0 in a baseball game, Tuesday, Sept. 11, 2012, in Houston. (AP Photo/Pat Sullivan)