Vargas scattered four hits through seven scoreless innings, Erick Aybar and Howie Kendrick each hit two-run doubles, and the Los Angeles Angels coaxed a pair of bases-loaded walks out of Jake Peavy in the fourth inning of a 6-2 victory over the Chicago White Sox.
Vargas (3-3) struck out six and walked three while helping the Angels gain a split of the four-game series. The middle of the Chicago lineup -- Alex Rios, Adam Dunn and Paul Konerko -- was a combined 0 for 8 with a walk against the left-hander, who posted his first victory in six career starts against the White Sox.
"When you've got three guys like that in a lineup, the biggest key is just to try and keep guys off base when they come up to the plate because it limits the damage that they're able to do," Vargas said. "When you can do that, you have more confidence in what you can go about doing with them, and there's more room for error."
Peavy (5-2) gave up four runs, four hits and five walks over six innings after going 4-0 with a 2.10 ERA in his previous five starts. The 2007 NL Cy Young winner is 0-4 with a 6.06 ERA in six career starts against the Angels.
"I felt really good today, and that's the most frustrating part for me," Peavy said. "I went out there with a good game plan and felt like we could execute, but I just didn't quite execute well enough. My slider was the best it's been all year, so I've got some positives to take out of it. It's just hard to be positive right now."
Los Angeles opened the scoring in the third when Iannetta drew a leadoff walk, J.B. Shuck followed with a single and Aybar drove both of them in with his double to right before he was erased in a rundown.
"Obviously the walks are going to kill you, especially leading off an inning. There's no excuse for that," Peavy said. "I have all the respect in the world for Chris Iannetta. He's got a great eye, there's no doubt about it. But good eye or nothing, I've got to throw the ball where he has to swing the bat."
Peavy, who threw 83 of his 117 pitches in the first four innings, walked four more batters in the fourth -- including Iannetta and Aybar with the bases loaded -- and the Angels increased the margin to 4-0. Two innings later, Peavy struck out the side on 18 pitches.
Iannetta's second walk was his 14th in a span of 33 plate appearances, including four on Saturday. He has 27 overall, just two fewer than he had last season in 221 plate appearances. His career high is 70, with Colorado in 2011.
"He's walking a lot," manager Mike Scioscia said. "I mean, if you look at Chris' history, there's no doubt the walk is in his game. Even when he was going through that little rough spot earlier in the season, he still drew some walks. I think it's great plate discipline, especially when you're not swinging the bat that well."
Rios drove in Chicago's first run with an eighth-inning double against Dane De La Rosa. It extended his hitting streak to 14 games, eclipsing his previous best in 2006 with Toronto.
Ernesto Frieri was called in to protect a 4-1 lead, trying to get his second four-out save in two days after giving up a three-run homer in the eighth against Hector Gimenez on Saturday before closing that one out.
The right-hander walked three batters in the ninth this time before notching his ninth save in 10 attempts overall. Frieri gave up a sacrifice fly by Alejandro De Aza before retiring Alexei Ramirez on a flyball to end it.
Kendrick gave Frieri a couple of insurance runs in the eighth with his double inside third base against rookie Brian Omogrosso.
Peavy had issued eight walks in 45 2/3 innings over his seven previous starts this season. The three-time All-Star, who led the NL in strikeouts in 2005 and 2007 with San Diego, got the 1,800th of his career in the first inning when he caught Mike Trout looking. ... INF Chris Nelson was added to the Angels' 25-man roster, one day after he was claimed off waivers from the New York Yankees. They are the third team he's been with this season, including Colorado. ... The Angels optioned 3B Luis Jimenez to Triple-A Salt Lake, and sent outright RHP Barry Enright to Salt Lake after he cleared waivers. Enright had been designated for assignment on May 16, one day after giving up four runs in two-plus innings against Kansas City in a 9-5 loss. ... Dunn returned to the lineup as the designated hitter, after leaving Saturday's game in the fifth inning because of back spasms. He finished 0 for 3 with three strikeouts and a walk. ... The White Sox return home to start an eight-game homestand on Monday against Boston.