MILWAUKEE -- There have been stretches of underachievement, a barrage of injuries and big asks of new contributors. Yet the St. Louis Cardinals enter September having navigated it all right back to familiar spot.
The three-time defending National League Central champs aren't exactly where they hoped to be. Another division title is all but out of reach. But as the Cubs cruise toward October, the Cardinals have put themselves in position to join them there again.
The Cards have a grip on the NL's second Wild Card spot and sit two games behind the Giants in the race for home-field advantage in that game. The two will meet in an upcoming four-game series (Sept. 15-18) that could weigh heavily on those final standings.
Thirty games stand between the Cardinals and a franchise-record sixth straight trip to the postseason. They'll begin that final push in Cincinnati on Friday. Here is a look at nine keys that will likely to define the team's finish.
3 crucial players
1. Adam Wainwright
No one has endured more extremes this season than Wainwright, whose mostly forgettable April and August runs have led the staff ace to declare this the worst season of his career. But he closed out August with a dominant performance, reminding St. Louis what he can be. With three pitchers ages 24 or younger in the rotation, the Cardinals need their most experienced starter to set the tone.
2. Aledmys Díaz
A broken thumb knocked him out of the lineup in July, but the All-Star shortstop is nearing a return. Plugging Diaz back into the two-hole will only deepen an already imposing lineup. He received clearance to resume swinging this week and is poised to begin a rehab assignment within days. Diaz could be back in St. Louis by the second week of September.
3. Alex Reyes
Whether he's in the rotation or the bullpen, Reyes' arm will be a big one. He opened his Major League career with 14 scoreless innings and has stepped into the rotation while Mike Leake recovers from shingles. Reyes, like Luke Weaver, is going to be asked to pitch meaningful innings down the stretch, and early returns are that he's ready.

3 reasons to believe
1. Been there, done that
The Cardinals feature a roster of players who know what it's like to step up when the stakes are the greatest. Since manager Mike Matheny took over in 2012, the Cards' September winning percentage is .596, second best among all NL teams. Every one of Matheny's teams has played its way into October.
2. Power and pinch-hitting
The Cardinals pace the NL with 189 homers and feature 10 players with at least nine home runs. Their success off the bench is equally as impressive. The club has tied the Major League record for pinch-hit home runs (14) and is hitting .328 in pinch-hit spots.

3. Getting healthy
The club is poised to make several key September additions, beginning with the return of power-hitting first baseman Matt Adams. Diaz shouldn't be too far behind, and Matt Holliday is eyeing a comeback as well. Brayan Peña has positioned himself to contribute as a bat off the bench, and the Cards haven't ruled out boosting their bullpen with Trevor Rosenthal and/or Michael Wacha at some point.
3 looming questions
1. Home (un)sweet home?
Despite boasting baseball's best road record, the Cardinals have not found a way to replicate that success at Busch Stadium. After averaging 52.5 home wins over the last five seasons, the Cards enter September with a 30-37 home record. They've got 14 home games remaining -- including three potentially critical ones against the Pirates -- to turn that around.
2. Will the rotation stabilize?
The team's most recent series in Milwaukee was a good first step, as the Cardinals received three quality starts. Carlos Martínez enters the month looking sharp. Weaver and Reyes have looked like capable contributors. Better start-to-start consistency from Wainwright and Jaime García is also necessary.

3. Can they get out of their own way?
The issues that have held the Cardinals back this season have been largely self-inflicted, be it porous defense or reckless baserunning. If they can minimize the mistakes, the Cards should fare better in close games. They are 20-19 in games determined by one run.
The road ahead
The Cardinals' run of three consecutive National League Central titles is ending, but the club still has its sights set on securing a postseason berth for the sixth straight season.
• Home games: 14
• Road games: 16
• Games vs teams over .500: 16
• Two key series: Sept. 15-18, at Giants; Sept. 30-Oct. 2 vs. Pirates
• Help on way? All-Star shortstop Diaz, who has been out with a fractured right thumb since July 31, is eyeing a mid-September return.
• Cause for concern: Their rotation is cracking. Wacha and Leake are on the DL, and Wainwright looks like a shell of his former self. The Cards go into September leaning on two rookie starters.