Before the St. Louis Cardinals went on this historic run rattling off 16 straight wins, their chances of reaching the postseason were projected to be less than 3 percent.

FanGraphs' playoff odds gave the Cardinals just a 2.8 percent chance to make the playoffs on Sept. 7. Now, they're a game away from clinching the National League's final wild-card spot.

It would mean they face whoever loses the NL West slugfest between the San Francisco Giants and Los Angeles Dodgers.

Neither team should be looking forward to this. Not even home-field advantage seems to factor much against this Cardinals team that's won 11 straight road games within their overall 16-game streak.

St. Louis is hitting for power, playing elite defense and getting solid performances from aging pitchers.

Tyler O'Neill has emerged as a star, hitting 11 home runs in September with three games left to play in the month. O'Neill has four homers and 11 RBI in the last eight games, but he's been getting it done all year. He also has a case for being the best defensive left fielder in the game.

Trading for Nolan Arenado, one of the best third basemen to ever do it, has paid off. Between O'Neill, Arenado, center fielder Harrison Bader, second baseman Tommy Edman, shortstop Edmundo Sosa and catcher Yadier Molina, the Cardinals field some of the best players at their respective positions in the National League.

Jon Lester and J.A. Happ were much-needed additions at the trade deadline from the Washington Nationals and Minnesota Twins, respectively.

Adam Wainwright is having one of the best seasons of his career in his 16th in the majors.

If the Cardinals are going to make a run, it will be behind Wainwright and against the Dodgers and Giants in some order.

Wainwright vs. Dodgers

The potential for a Wainwright vs. Max Scherzer duel makes this wild-card possibility so compelling.

When Wainwright pitched against the Dodgers on Sept. 8, he allowed three consecutive hits in the first inning, then put down 15 in a row before giving up a solo home run to Max Muncy. 

Wainwright tried to hang in there for his fourth complete game of the season and the 28th of his big league career, but the Dodgers chased him in the ninth. 

The Cardinals held on to win 5-4. It had a postseason feel and played out how you might imagine a single elimination could. 

The difference is having Scherzer starting for the Dodgers in the wild card, unlike the Sept. 8 matchup against Mitch White.

Wainwright vs. Giants

The Cardinals won Wainwright's first start against the Giants on July 6 largely because of their offense. Arenado and Sosa both homered, and first baseman Paul Goldschmidt had a two-run single the lead the way.

Wainwright gave up three earned runs on seven hits in five innings, but St. Louis beat the Giants 6-5.

Ten days later, Wainwright whiffed seven Giants and also gave up a pair of home runs in a loss.

At that point, the Cardinals' season looked bleak. The trade deadline was still a couple of weeks away, and it wasn't yet clear what kind of team this would be.

Cardinals defense can swing a game

Wainwright has benefited from his defense more than any big league pitcher this season, per Baseball Savant. The 23 outs above replacement produced behind Wainwright is by far the most, with the Cleveland Indians' Cal Quantrill trailing with 10 OAA.

The Cardinals defense has prevented 19 runs behind Wainwright, which is also more than any other pitcher. Next closest is the Houston Astros, preventing eight runs from Jose Urquidy's pitching.

In September, two of the Cardinals' pitchers are top four in OAA—Wainwright and Miles Mikolas, who is No. 1, per Baseball Savant.

As a team, the Cardinals have prevented 37 runs and 47 OAA, both league highs. The only other comparable team defensively is the Houston Astros (35 and 42, respectively), after which there is a significant drop-off.  

Individually, O'Neill, Edman, Arenado, Goldschmidt and Bader are consistently among the OAA leaders at their positions.

More than just St. Louis offering a renaissance collection of Wainwright, Lester and Happ, the Cardinals defense can swing a single game.

The long ball is a threat

Only the Toronto Blue Jays have hit more home runs in September than the Cardinals.

Over the course of the winning streak, St. Louis has homered 31 times.

The Cardinals are homering with runners in scoring position more than anyone this month aside from the Blue Jays.

For the past month, the Cardinals have the second-highest slugging percentage (.489) with runners in scoring position, again only trailing the Blue Jays.

Goldschmidt has the second-highest OPS (1.330) over the last 15 days, with Bader coming in sixth (1.154). It was this tandem that hit the home runs in Sunday's 4-2 win against the Chicago Cubs to raise the Cardinals' September home run total to 47.

That broke a club record set by Mark McGwire's 1998 team for most home runs in the September/October portion of the regular season.

Factoring in the pitching, defense and what the Cardinals are doing at the plate, they do everything well enough to spoil a 100-win season.