CHICAGO • As rookie reliever Seth Maness continued to turn pitches into outs at an uncanny rate and buy time for a Cardinals rally Wednesday as a result, several of his teammates sat in the dugout and tried to do the math on the kid’s potential.

On his first eight pitches in the big leagues, Maness had five outs and a win.

On his first 10, he had nine strikes and seven outs.

“Is it possible for him to get 100 wins with less than 100 pitches?” ace Adam Wainwright recalled musing with his fellow pitchers on the bench.

“I’m not good enough at math for that,” fellow starter Lance Lynn joked.

Maness has defied equations by making one equal two, which he did again Wednesday as he coaxed two double plays and pitched 1 2/3 scoreless innings.

His was the longest outing from a bullpen that drew three key double plays and allowed the Cardinals to muster a 5-4 victory against the Cubs at Wrigley Field.

Jon Jay’s single drove home Yadier Molina in the eighth inning to snap a 4-4 tie, but the difference in the game for the Cardinals was their retooled relief.

Since his debut on Friday as part of the new-look bullpen, Maness has two wins and 10 outs, all on a total of 18 pitches. Like Maness, the Cardinals’ bullpen has had a quick and efficient turnaround.

Less than a week after two renovations, Cardinals relievers inherited a one-run deficit from starter Jake Westbrook in the sixth inning.

Four relievers, including lefty Randy Choate and closer Edward Mujica, combined to throw 32/3 scoreless innings. That gave the offense time to tie the score on Carlos Beltran’s third hit, then win it on Jay’s second RBI.

“I love those wins,” Cardinals manager Mike Matheny said. “We wear out the word ‘perseverance,’ but you just see back and forth and there are teams that roll over. This one kept playing the game. This was a great example of the bullpen coming in — they’re going to pick us up at times.”

The Cardinals return to Busch Stadium for a series that opens Friday having gone 5-1 on the quick visit to two National League Central rivals.

It is the first time the Cardinals have been away from home for more than three games and returned with one or no losses since August 2010.

The Cardinals have won eight of their past nine road games, and their 14 wins on the road are the most in baseball.

But the team that returns home looks a little sturdier, a little deeper than the one that left only six games ago.

The Cards have reinvented on the go. Two of the upgrades contributed to the win Wednesday.

When he last played at Busch, center fielder Jay had yet to surface from a slump so profound and extended that it forced him to do the unusual — change his swing on the job.

Jay went hitless in four at-bats in the Cardinals’ last home game, falling to four for 36 (.111) with seven strikeouts in his previous 12 games.

He has a new swing since then.

He has at least one hit in every game since.

“It’s a drastic difference,” said Jay, who steadied his hand position at the start of his swing, eliminated a hand pump and elevated his average from .204 to .257 on the six-game trip.

Matheny moved Jay up in the order Wednesday, to No. 6, to provide “protection” for Molina.

He delivered two RBIs against the Cubs as the Cardinals steadily stayed in the game.

Leadoff hitter Matt Carpenter and No. 2 hitter Beltran combined to reach base seven times. The Cardinals scored one run in five innings. In the fourth inning, Allen Craig raced from first base to third on Molina’s single so he could score on Jay’s sacrifice fly. In the eighth, Molina took second on a wild pitch from reliever Michael Bowden (1-2). He scored when Jay lashed a single to right field.

Lefty specialist Choate got a double play from lefthanded hitter Nate Schierholtz to end the eighth inning and preserve the one-run lead.

Three of the Cardinals’ double plays came with a runner in scoring position, and two — forced by Maness and Choate — came with a runner at third and ended an inning to keep the run from scoring.

Mujica pitched a perfect ninth for his ninth save.

As recently as last Thursday, the first day of the trip, the bullpen was radioactive. Matheny relied on two pitchers, Mujica and Trevor Rosenthal, because others had struggled.

Through last Thursday, the bullpen’s earned-run average was 5.78, the worst in the majors. That day the Cardinals continued to remake the bullpen on the fly by demoting Mitchell Boggs. Last Friday, newcomers Maness and Carlos Martinez both made their big-league debut. Since then, the bullpen has allowed one run in 121/3 innings (0.73 ERA).

Matheny said the bullpen is still a work in progress.

But at least it works.

“We talked about how it could look a whole lot of different ways,” Matheny said. “It’s a lot of moving pieces right now. I think it’s going to be stick-and-move. That’s where we are.”

Matheny described how there will be ballparks, such as Milwaukee’s and Wrigley with the wind blowing out, where his relievers with flyball tendencies might not succeed.

He still is experimenting with the best way to utilize hard-throwing Martinez. Maness has been swift to find a spot. An unerring righty, Maness has a sinking fastball designed to get the double-play grounders with runners on base. He showed his comfort with runners on base during spring training, the first time the lifelong starter had tried that kind of relief.

With a similar sinker-based approached, Maness said he likes to watch Westbrook work, as he did for 51/3 innings Wednesday.

The Cubs tagged Westbrook for three runs in the fourth, but the veteran continued to rely on his sinker and finished the inning with three groundouts.

Maness relieved Westbrook with two runners on base in the sixth inning. The rookie’s first pitch was a ball. The next resulted in a double play to end the inning. Another double play in the seventh put him in position to get the win.

For now that’s how the Cardinals’ relief adds up.

“Just kind of the right place, right time,” Maness said.

Derrick Goold covers the Cardinals and Major League Baseball for The Post-Dispatch. Follow him on Twitter at @dgoold or on Facebook at Facebook.com/BirdLandPD

Derrick Goold is the lead Cardinals beat writer for the St. Louis Post-Dispatch and current president of the Baseball Writers' Association of America.