The worst team at getting on base in the American League just might be the last team anybody wants to face in a postseason series. The Seattle Mariners are the right team at the right time, having exploited the run-depressed environment of today’s game as well as anybody. The Mariners’ pitching staff is so good that it could be the toughest to hit in the 42-season history of the designated hitter.

That’s right. It’s not the Athletics with Jon Lester or the Tigers with David Price that can shut down offenses better than any staff in either league since 1972. It’s the Mariners, a team that can’t hit and hasn’t seen the playoffs since 2001, who began this week holding opponents to a .224 batting average, the lowest in the majors since pitching so dominated the game the AL owners fundamentally changed the sport by adopting the DH.

Seattle is winning with Deadball Baseball. Its team ERA is 2.94, including 1.89 this month. Think about that: 2.94 in the AL! My, how much the game has changed. As recently as 10 years ago, the Twins led the league with a 4.03 ERA. The Mariners' ERA is so low it would have led the AL way back in its first season of 1901, when the ball (one per game might do) didn’t have a cork center and was likely covered in dirt, saliva, tobacco juice or slippery elm.

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Surprised? I wrote before the season started that every year we get at least one team – and usually at least two – that find their way into the playoffs the season after posting a losing record. And of the 14 losing teams from 2013, I told you the Mariners (71-91 last year) had the best shot at making the postseason this year. (My second, third and fifth choices were the Giants, Angels and Brewers, all of whom also have a good chance at the postseason.)

What I liked about Seattle was its change in managers (Eric Wedge to Lloyd McClendon), the likelihood that the team’s terrible record in one-run games would turn around (though it hasn’t, from 19-29 to 14-22) and a core of players just entering what should be their prime years.

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But this? A staff that is holding hitters to a .287 OBP, the lowest in the league since the 1972 Orioles and Athletics? A 13-man staff in which the ace (Felix Hernandez) and closer (Fernando Rodney) earn $29.9 million and the 11 other guys make $12.9 million? A staff with one guy who was out of baseball for five years (Tom Wilhelmsen, 30), another who last pitched in the majors three years ago (Joe Beimel, 37) and a third who last pitched in the majors two years ago (Chris Young, 35)?

Let’s face it: King Felix you know, but the likes of Roenis Elias, Danny Farquhar, Dominic Leone and Brandon Mauer wouldn’t turn heads if they showed up at the Space Needle with their jerseys on.

“We’re carrying eight pitchers in the bullpen,” said Mariners GM Jack Zduriencik. “We have the extra arm quite frankly because all of them have been so good, nobody deserved to be sent down. It works out great because it gives Lloyd enough options so nobody gets worn down.”

The Mariners’ pitching staff is the result of exploiting just about every run-prevention methodology that has created the greatest pitching era in 40 years: hard throwers with an extra-deep bullpen backed by advanced analytics and a defense featuring the kind of rangy athletes who were effectively drummed out of the game in the Steroid Era. It helps, too, that Seattle plays its home games in a pitcher’s paradise, Safeco Field.

First, let’s define just how historically good this Mariners’ staff is. Check out where the Seattle pitchers rank in three key categories among all MLB teams since 1973 (all stats as of the start of this week):

Lowest Batting Average Against

1. 2014 Mariners: .224

2. 1975 Dodgers: .225

3. 1986 Astros: .225

4. 2012 Rays: .228

5. 1973 Dodgers: .231

Lowest OPS

1. 1981 Astros: .599

2. 1975 Dodgers: .612

3. 1988 Mets: .620

4. 1988 Dodgers: .626

5. 1976 Mets: .628

6. 2014 Mariners: .633

Lowest WHIP

1. 2014 Mariners: 1.125

2. 1975 Dodgers: 1.132

3. 1976 Mets: 1.150

4. 1988 Mets: 1.151

5. 1981 Astros: 1.154

That’s just crazy good. Notice that there is only one other AL staff on those lists, which isn't a surprise because those teams regularly face the DH, not the pitcher. So how do the Mariners do it? Rewind to last season, when Zduriencik was so hungry to inject power into a feeble lineup that he gave opportunities to defensively-challenged players such as Jason Bay, Raul Ibanez, Jesus Montero, Kendrys Morales and Michael Morse. Seattle did hit the second-most homers in the league, but its defense suffered. The Mariners ranked 23rd in the majors in batting average on balls in play (.305).

“I’ve always been cognizant of defense, but last year we got away from it,” Zdruriencik said. “Last year was a stopgap year, the bridge year.”

He pointed to major changes and improvements to the defense this year: the addition of second baseman Robinson Cano, the emergence of catcher Mike Zunino (“The leadership and toughness he brings has been huge”), the improvement of Dustin Ackley in leftfield (“[Coach] Andy Van Slyke deserves a tremendous amount of credit”), the surprising work at first base by Logan Morrison (“He’s better defensively than I thought”) and the way the players have embraced pitching and defense as the team’s identity.

“We have infield practice every homestand and guys really work at it,” Zduriencik said. “The staff has put in so much time and effort on defense and the players really bought in. They really like it. And they see the results.”

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Here’s the most obvious result: the Mariners have improved from 23rd in the majors on BABIP (.305) to first (.270).

The Mariners have benefited from luck, too. In a year in which one of the most oft-mentioned pitchers is Tommy John, they have been unusually healthy, needing only 19 pitchers all season; only the Nationals and Giants have used fewer. And there are many pleasant surprises among the ones they have used.

Young (12-6, 3.07), cut by Washington late in spring training, found the perfect home in Seattle as a 6-foot-10 flyball pitcher whose 86-mph fastball at the top of the zone baffles hitters. “We always liked him,” Zduriencik said, “but I’d be lying if I said we expected this.”

Rookie James Paxton (3-0, 2.20), sidelined for much of the year with a lat problem, has given the team a jolt with a fresh arm that is not bound by innings limits. “Now he looks like a guy who just got out of spring training,” Zduriencik said.

Elias (9-10, 4.09), another rookie, is a 26-year-old lefthander out of Cuba who was signed three years ago. He has been serviceable once coaches convinced him to stop inventing pitches and arm angles mid-game the way he did in the minors.

Hisashi Iwakuma, who was so bad in his walk year in Japan he was sent to the minors, has been brilliant since adopting the Mariners’ shoulder strengthening program once he arrived in the U.S. before the 2012 season. His 2.81 ERA over the past three years is the best in the AL (minimum 400 innings) with one exception: the indomitable Hernandez, 28, who is having a career year (again). In addition to leading the league in ERA (1.99) and WHIP (0.87), Hernandez's changeup is so nasty that he has allowed only 23 hits on the 797 times he has thrown the pitch this year.

Can a team that scores less than four runs per game and posts an OBP of .302 really be a feared postseason team? We have seen it before: of course, it was 108 years ago, smack in the Deadball Era. The Chicago White Sox, known as “The Hitless Wonders,” posted a .301 OBP in 1906. They won the World Series.

These Mariners have a bit more than the seven home runs the Hitless Wonders hit that entire season, but you get the point. The game has changed so much in favor of run prevention that the worst team in the league at getting on base actually has a shot at the postseason.