The White Sox used a four-run seventh inning, featuring two hits by Joe Crede, to take an 8-2 lead, but needed a leaping catch by Iguchi on Mark DeRosa's bases-loaded line drive in the eighth inning to hold on for an 8-6 victory.
"That won the game," said White Sox closer Bobby Jenks, who covered his face with his glove after Iguchi made the catch. "I didn't say one word. I was thinking in my head, `I can't believe he caught the ball."'
The Rangers had two on and no outs when Jermaine Dye grabbed Gary Matthews Jr.'s hard liner to right for the first out in the eighth.
Michael Young then singled to load the bases before Matt Thornton got Mark Teixeira to pop out. Hank Blalock's RBI infield single made it 8-6 before Iguchi went high to snag DeRosa's liner to second and end the inning.
"DeRosa put a good swing on a ball that might have split the gap and scored all three," Rangers manager Buck Showalter said.
"He made a really good play. That's really all you can do," Matthews said of Iguchi's play. "DeRosa squared up a ball on Jenks, who's tough. The balls just didn't fall in."
Jenks then got the final three outs in the ninth for his 15th save in 16 chances.
"If he (Iguchi) doesn't make that play, we're in big trouble. He saved the game," White Sox manager Ozzie Guillen said.
"I was able to get good positioning," Iguchi said through a translator. "Actually catching the ball wasn't that big of a deal, but getting the position I was in was lucky."
Javier Vazquez (7-3) gave up 11 hits and five runs over 6 1/3 innings en route to his third straight victory.
With AL home run and RBI leader Jim Thome sidelined for a second straight night with a groin strain, the White Sox collected nine hits, six of them in the fourth when 12 batters came to the plate.
After Crede hit his leadoff double, he moved up on a ball-four wild pitch to Rob Mackowiak and scored when Alex Cintron hit an RBI fielder's choice grounder that went off second baseman Ian Kinsler, who threw late to second trying to get the force out. That tied the game at 2-2 and after a sacrifice, Scott Podsednik laced a two-run double inside the bag at third. Moments later he stole third and scored on Iguchi's RBI single off Vicente Padilla (5-4).
After reliever Joaquin Benoit walked Dye to load the bases, A.J. Pierzynski had an RBI single for a 6-2 lead. Crede followed with a two-run single to make it a six-run lead.
"They stayed away from the big inning for the most part and we didn't," Showalter said. "They did a lot of things well in that (fourth) inning."
The Rangers responded with three quick runs in the fifth as Young, Teixeira, Blalock and DeRosa hit four straight singles and Brad Wilkerson had a sacrifice fly to cut the lead to 8-5.
Vazquez had to sit for quite a while during the White Sox's long rally but had no complaints.
"It cools you off, no doubt, when you score that many runs," he said. "But I prefer that to anything else."
The Rangers scored twice in the third but could have had plenty more after loading the bases with no outs on successive singles by Rod Barajas, Matthews and Young. Vazquez then walked Teixeira on a 3-2 pitch to force in a run and gave up an RBI single to Blalock with the bases staying loaded. But DeRosa struck out before Wilkerson and Kinsler hit back-to-back popups to second baseman Iguchi.
Chicago took a 1-0 lead in the first on a double by Iguchi and an RBI single by Paul Konerko on a ball that went up the middle and hit the second base bag, ricocheting into the outfield.
Padilla lasted 3 1/3 innings, giving up seven hits and seven earned runs.
The White Sox have given Vazquez a lead in all 11 of his starts this season. ... The seven runs were the most scored in an inning by the White Sox since plating 10 against Arizona on June 15, 2005. ... Matthews was 3-for-5 for Texas and is 10-for-21 in his last five games. ... Blalock was also 3-for-5 and had three RBI.