CHICAGO -- One week after clinching the National League Central title, the Cubs are focused on fine-tuning some things in preparation for the postseason. The Cardinals, on the other hand, have to beat their division rival if they hope to secure an NL Wild Card berth, and they were unable to do so on Friday afternoon at Wrigley Field.
Jake Arrieta struck out 10 over seven innings in the Cubs' 5-0 victory over the Cardinals, their 15th shutout of the season. It was Chicago's 98th win, the most in a single season since winning 98 in 1945, which was the last time the Cubs played in the World Series. Though they lost, the Cardinals remained a half-game behind the Giants, who lost to the Padres, for the second NL Wild Card spot.
"You keep an eye where you're at, but at the end of the day, you just try to win," Cardinals starter Mike Leake said. "If you're winning, then you don't have to worry about what the other teams are doing."
With the win and the Nationals' extra-innings loss in Pittsburgh, the Cubs clinched the NL's top seed, guaranteeing them home-field advantage throughout the NL playoffs.
Arrieta is now tied with teammate Jon Lester and the Nationals' Max Scherzer for the NL lead in wins with 18.
"That was more reminiscent of what we saw last year," Cubs manager Joe Maddon said of Arrieta, the reigning NL Cy Young Award winner. "He's not 100 percent there, but that was pretty darn good. [The Cardinals are] a good hitting lineup. That lineup they threw out today was a great test to see where he's at."
Anthony Rizzo hit an RBI double and scored on Ben Zobrist's single in the four-run first inning to give Arrieta all the support he needed. Leake was lifted after 3 1/3 innings, matching his shortest outing of the season. Behind him, six Cardinals relievers held the Cubs scoreless the rest of the way.

"If we don't have the first inning that we have and are able to hold them close, you never know what happens with our club," Cardinals manager Mike Matheny said. "But [Arrieta] was not giving a lot of anything. Being down four to a good team puts your back against the wall. It's not an easy assignment anytime, let alone against a guy who just won a Cy Young."
• Sloppy start downs Leake, Cardinals in opener
MOMENTS THAT MATTERED
Start me up: Arrieta erased any doubts about his command or velocity. He walked one and scattered five hits in his longest outing since Aug. 23, and he notched double digits in strikeouts for the fourth time this season. Arrieta continued to stymie his former TCU teammate, Matt Carpenter, as well. Carpenter went 0-for-4, and he now is 0-for-24 in his career in the regular season against Arrieta.

Arrieta was matched up with catcher Miguel Montero for the first time in a while, and it may have helped him get back on track.
"We work well together," Arrieta said. "[Montero] knows the way my stuff works and he has little mannerisms that help me get back on track from time to time. It's nice to have a guy like that who can pick things out visually." More >
Judgment call: St. Louis' best chance to chip away at Chicago's early lead came in the third, which opened with consecutive singles by Jhonny Peralta and Kolten Wong. Leake squared to bunt, took a pitch off his knuckles and began heading toward first. But instead of loading the bases with no outs, Leake was summoned back after home-plate umpire CB Bucknor ruled that Leake had not pulled the bat back on the bunt attempt. The Cardinals could not challenge the call, and Leake proceeded to bunt into a rally-squelching double play.

"I'd like to see them [take a second look at] anything that's a pivotal point in the game that can be reviewed," Matheny said. "We're cooperating with trying to speed the game up, but not at the cost of getting the game right. Not at the cost of using technology in a way that can get it right and help them out. Not to say that's the end-all be-all. I know we still had a long way to go to get back into that one. But that's a pivotal point in the game, and it's frustrating when you can't get it right."
First things first: The Cubs jumped on Leake early. Dexter Fowler walked to lead off, reached third on Kris Bryant's single and scored on a wild pitch. Rizzo followed with an RBI double, and he scored on Zobrist's single. Two outs later, Chris Coghlan hit an RBI double down the right-field line to open a 4-0 lead. The Cubs now have outscored their opponents by 43 runs (105-62) in the first inning.

"Our offense can go on an outburst at any moment in time," Arrieta said. "If I'm able to pound the strike zone and mix in offspeed for strikes from the get-go, you combine that with our offense's ability to score runs in bunches, that puts us in a good spot."
Slip up: The Cardinals had all sorts of first-inning issues, and perhaps they were best summed up with one ungraceful slip by Wong in left field. Wong, making his third career start at that position, caught his cleat in the grass as he pursued Rizzo's hit and took a tumble while the ball squirted away. Rizzo ended up on second with an RBI double. It was one of three plays not made by the Cards' defense in the inning, which was further compounded by two wild pitches.
"You have to be aggressive in that situation," Wong said. "If I catch that ball and don't fall, there's a chance I put a play on at home plate. As soon as I put my foot down, it was out. There was no stopping it. That thing lifted up right away. I didn't realize that they replaced the turf not too long ago."
QUOTABLE
"When you're a guy who's a backup catcher and kind of a journeyman and has been on a bunch of different teams and trying to find your way through the Major Leagues and do the best you can, [to] get a moment like that is pretty cool." -- Cubs catcher David Ross, who is retiring after this season and was honored pregame with gifts, including home plate from Arrieta's no-hitter in AprilMore >

"When you start worrying about other teams, you get caught up in them instead of worrying about yourself. We can only take care of what we can take care of. The rest, let it fall as it will. We have no control over how they're going to play. We can only control how we play." -- Wong, on keeping tabs on the other NL Wild Card contenders
SOUND SMART WITH YOUR FRIENDS
The Cubs tied a franchise record with their 56th win at home. They also won 56 home games in 1933 and '35.
WHAT'S NEXT
Cardinals:Alex Reyes, who threw seven scoreless innings in a win over the Giants last weekend, will return to the mound on Saturday at 12:05 p.m. CT to start the second game of the Cardinals' final regular-season visit to Wrigley Field. Reyes has pitched 7 1/3 innings of relief against the Cubs this season, and he has not allowed a run.
Cubs:Jason Hammel will start the second game of this three-game series against the Cardinals. He is 10-1 with a 1.84 ERA in 14 home starts. In Hammel's last outing against the Reds, he gave up two runs over seven innings.
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