"That's three in a row and two in this series against two good starters," Arrieta said of the Cubs beating the Cardinals' Adam Wainwright on Friday and Michael Wacha on Saturday. "But we have good guys, too. We have some guys who can compete at that level and put up some good performances."
It's the Cubs' first series win since they took two of three against the Reds last Sept. 9-11.
"It feels good -- it just feels good to win a ballgame," Cubs manager Rick Renteria said.
Reliever Brian Schlitter picked up his first Major League win, and received the traditional beer shower as a reward. He took over for Arrieta, who was making his first start of the year after being slowed this spring because of tightness in his right shoulder. On Saturday, the right-hander struck out seven over 5 1/3 innings, and was pulled after throwing 82 pitches.
"I thought he maintained his strength throughout," Renteria said of Arrieta. "Coming back from such an extended recovery, we were going to make sure we took care of him."
This was only the Cardinals' second look at Arrieta, who faced them last Aug. 16 at Wrigley Field and gave up two hits over seven scoreless innings. That was his second start for the Cubs, who acquired the pitcher from the Orioles in the Scott Feldman deal.
"He had good life on the ball and it just wasn't one side," Cardinals manager Mike Matheny said. "He was moving the ball around, had a lot of movement going away from right-handed hitters, and times you could see them taking some uncomfortable swings."
Arrieta admitted he had a few butterflies.
"I think a lot of it had to do with pitching back at Wrigley for the first time," Arrieta said. "It's pretty special pitching here. After I played catch and got in the bullpen, it was kind of business as usual."
The Cardinals threatened in the first, and had runners at first and third with two outs, but Arrieta struck out Yadier Molina to end the inning. The Cubs had a runner at third with two outs in the fourth and Wacha got Welington Castillo to fly out to right.
The Cubs loaded the bases in the fifth but Wacha got Rizzo to ground out. Matt Adams singled with one out in the Cardinals sixth to chase Arrieta, and Schlitter got both Molina and Jhonny Peralta to fly out.
The Cubs finally came through in the sixth. Starlin Castro singled to lead off, and two outs later, Lake connected on his third home run off a 2-1 pitch from Wacha, launching it into the bleachers in left-center. Lake entered the game 5-for-31 in his last 10 games.
"I didn't think about anything, just look for my pitch," Lake said. "If they throw my pitch, I said, 'I got it.'"
"Wacha was good today," Rizzo said, "and he got himself into some trouble but worked out of it a few times. Junior, that home run is huge for us. That was it, that was the deciding factor."
Rizzo made it 3-0 when he led off the eighth against Randy Choate with his sixth home run and third this season off a lefty. The Cubs first baseman now has homered in three straight games, and was batting .400 (20-for-50) in 15 home games.
"We're swinging the bats with some production," Renteria said. "I think we're playing pretty good defense and the starting pitching has done a pretty good job of keeping us in the ballgame. It doesn't hurt that to this point, the bullpen has stabilized a little bit. They've done a nice job when we've asked them to do what they've needed to do."
The Cardinals made it interesting in the ninth. Molina and Peralta both singled off Hector Rondon, the closer of the day, and then Jon Jay hit a comebacker to the pitcher, who turned a 1-6-3 double play.
"Rondon's out there, and I call him 'Angry' because he looks angry on the mound," Rizzo said. "That comebacker is nice. It's textbook."
"I knew I needed to make a good pitch," said Rondon, who now has three saves, all against the Cardinals.
The Cubs haven't had a designated closer since April 11, when Jose Veras blew a two-run lead in St. Louis. Before the game, Renteria said the situation was "fluid." Now?
"It's organic still, as they say," Renteria said.
This is Renteria's first exposure to the Cubs-Cardinals series, and he's keeping an even keel approach.
"It's two games," he said. "There's a long season ahead of us. I'll measure up where we're at at the end of the season. Is it good to put these two games behind us? Sure. But it's a long season and we have to maintain our approach and keep playing baseball. Right now, we're in a good place."