CHICAGO -- It's been a crazy first half for Edwin Jackson, who seems to have found his groove.
Jackson held the Cardinals to three hits over seven shutout innings to win his third straight start and Anthony Rizzo had two hits and three RBIs to lift the Cubs to a 3-0 victory Thursday.
It was a rare win for the Cubs against a National League Central team. Chicago now is 14-26 against division rivals, the lowest winning percentage by any team against its own division.
The Cardinals boast the best record in baseball, but that didn't seem to faze Jackson. The right-hander, who helped St. Louis win the World Series in 2011, struck out five and did not walk a batter. This was the first start this season in which he did not issue a walk, and the first time since Sept. 21 with the Nationals.
It was a good ending to what has been an inconsistent first half for Jackson, who signed a four-year, $52 million deal this offseason, his first long-term contract.
"Tonight, he was really sharp against the best offense in baseball," Cubs manager Dale Sveum said. "He had a lot more conviction with his pitches, and wasn't worried about pitching as much as throwing. He pitched well tonight, had command, was hitting his spots, and had a really good slider. He got ahead, which I think was the biggest thing."
Jackson has done well against his former teams. This was his second start against the Cardinals -- he lost on June 19, giving up four runs in 5 1/3 innings -- but he has picked up a win over the Nationals, whom he played for last season, and gave up one hit and struck out three over 2 2/3 scoreless innings against another former team, the White Sox, on May 28, before rain stopped that game.
After opening the season 3-10 with a 5.84 ERA in his first 15 starts, Jackson now is 3-0 with a 1.93 ERA in his last three outings. How do you eliminate slow starts?
"If you had the answer to those things, we'd be a heck of a lot richer," Sveum said.
"This is probably the craziest start I've ever had in baseball," Jackson said. "It's a game of grinding it out and as long as you believe you have the confidence that you can come in and turn things around, that's all that matters. No one expected me to start like I did -- myself, the front office, the team, my manager. It's a game, you have to keep grinding. You can sink or you can swim. I'm definitely one of those guys who won't give up."
He could have. Teams were batting .286 against him in those first 15 games, and are hitting .203 in his last three.
"I never did lose confidence, even in the bad starts I had," Jackson said. "You just have to work harder to get back to where you want to be."
The win was the Cubs' fifth in their last six games. The Angels snapped the streak on Wednesday with a 13-2 romp. Chicago now has won 12 of its last 19 games.
With one out in the bottom of the first, Starlin Castro singled and then scored on Rizzo's double into the gap in right-center. It was the Cubs' 293rd extra-base hit, most in the National League.
Luis Valbuena walked to open the third, Castro singled again, and both moved up on a wild pitch by Jake Westbrook before scoring on Rizzo's single to left. Rizzo began the day with three RBIs in his last 34 at-bats.
The Cubs first baseman has had a streaky first half, but also is ending well. On Thursday, he seemed to have a calmer approach at the plate. Sveum has stressed to Rizzo to use his hands more than his body.
"That's the hitter I am is hands, and I did get into a big body move," Rizzo said. "I could take a big swing with all hands. That's what I'm really working on right now."
Jackson struck out David Freese to end the seventh and leave a runner at third. St. Louis had runners at second and third with two outs in the eighth, but Pedro Strop fanned Carlos Beltran with a nasty slider to end the inning. Kevin Gregg pitched the ninth for his 16th save as the Cardinals were shut out for the fourth time this season.
The game ended on an ugly note for Cardinals manager Mike Matheny, who was ejected by home-plate umpire Dan Bellino after arguing at the end of the game about how Bellino dealt with Matt Adams, who was called out on strikes to open the ninth. Matheny had to be restrained by crew chief Wally Bell.
"It had more to do with the umpire and how he mistreated one of our players, with Adams," Matheny said. "It had nothing to do with the call. It had everything to do with going too far."
Adams had said something after getting called out, and Bellino apparently didn't like it.
"That's not the story of the game," Matheny said. "Jackson pitched a good game against us. We've seen him a couple times do that and we couldn't put anything together."
The Cubs' bullpen has gone through a total makeover since Opening Day, and may finally have the right pieces.
"Our bullpen has really come around," Rizzo said. "I like the matchups we have with the big guys at the end."
Rizzo got the RBIs, but Sveum was happy with the way Castro played and the shortstop's energy on the bases. Sveum didn't want to share their discussions on hitting, but said Castro has been playing like "the best shortstop in the game the last week."
That also bodes well for the second half.
Carrie Muskat is a reporter for MLB.com. She writes a blog, Muskat Ramblings, and you can follow her on Twitter @CarrieMuskat. This story was not subject to the approval of Major League Baseball or its clubs.