CHICAGO (AP) -- In his second game with the Chicago Cubs, Jake Arrieta showed exactly why they're putting him in the rotation for the rest of the season.
The hard-throwing right-hander dominated the potent St. Louis Cardinals lineup for seven innings to lead Chicago to a 7-0 victory Friday.
"That's the kind of stuff the power arms can do when they're throwing strikes and making pitches and you have a 91 mph cutter, slider or whatever you want to call it," Cubs manager Dale Sveum said. "He made some really good pitches in some key situations of counts. When you thought you might be losing good hitters, he made some key pitches on the black at 95, 96 mph."
Arrieta (1-0) allowed two hits and two walks while striking out seven. After yielding an infield single to Carlos Beltran in the second, he got rookie Kolten Wong to ground into a double play.
That started a streak of 13 straight outs (including five strikeouts) until Arrieta walked St. Louis starter Jake Westbrook (7-8) in the sixth.
The next batter, Matt Carpenter, also walked to give the Cardinals their first threat of the game. But Jon Jay grounded into a fielder's choice and Matt Holiday struck out looking to end the inning.
In his only other start with Chicago, Arrieta allowed one run and two hits in six innings July 30 against Milwaukee. He's thrown 13 innings in a Cubs uniform and allowed one run. That's a far cry from the struggling pitcher who went 1-2 with a 7.23 ERA for Baltimore this season before he was traded to the Cubs on July 2.
So which one is the real Jake Arrieta? The struggling power arm or the dominant pitcher he was on Friday?
"That's what I'm capable of," Arrieta said. "It's just a matter commanding the ball and limiting my walks. That's really what's gotten me in the past was too many free passes, letting guys get away when I'm in favorable counts and pretty much keeping my foot on the gas and staying on the attack.
"I've made a conscious effort to get better at certain things and it's starting to show."
The Cubs got Arrieta all the runs he needed in the first inning. After Westbrook walked the bases loaded, cleanup batter Nate Schierholtz hit a two-run single to center. Donnie Murphy added a two-out RBI single to make it 3-0.
Chicago had been shut out in four of its past five home games.
"We got some big hits. I think the biggest was Nate's," Sveum said. "We've had chances like that this year when we couldn't come away with one (run) and to come away with the big hit there and then Murphy's two-out hit ... to get three runs on the board there was key in that game."
The 27-year-old Arrieta should be entering the prime of his career, but he's still trying to establish himself in the majors. He thinks the trade to the Cubs has given him a fresh start free of his struggles of the past.
"For me, there's no question that this change of scenery and this trade was huge for me in my career -- not only for me, but for the Cubs as well," he said. "I couldn't be more excited to be here and I'm thankful to the front office for wanting me and bringing me into this organization."
The Cubs snapped a four-game losing streak and are 7-7 this season against the Cardinals, who began the day trailing first-place Pittsburgh by two games in the NL Central.
Westbrook finished with five walks but managed to grind through 6 2-3 innings to save the bullpen. He allowed seven runs -- six earned -- and eight hits with two strikeouts.
"I was pretty much all over the place and the walks hurt you, especially when they're in a row with no outs," Westbrook said. "It wasn't very good. It's always frustrating when you don't give your team a chance to win and do your job, which I haven't been able to do the last couple outings."
Since coming off the disabled list June 14, Westbrook is 5-7 with a 5.86 ERA. After the loss, he said his arm feels fine.
Asked if Westbrook is certain to make his next start, Cardinals manager Mike Matheny was non-committal.
"We'll see how he feels tomorrow," Matheny said
"That's not what any of us were looking for," he added. "Talked about it before: Sometimes he just has trouble finding the release point for his sinker and he couldn't find it today until it was too late."