I feel like I’m holding a shovel in mid-air. After a season of insisting that the Yankees were a little bit of health, or some regression, or a slump by the Rays, or some combination of those things away from ascending in the AL East, I’ve been poised to join the group of writers, fans, and analysts set to bury their playoff chances. As I wrote yesterday, a loss to the Red Sox that put them eight games out in the wild-card chase with 29 to play would have caused me to start turning over some earth . . . but with the comeback, 3-2 win over the Sox, the Yankees are six games out instead of eight-a two-game swing that gives me pause.

Perhaps it shouldn’t. According to the latest Playoff Odds Report, the Yankees have just a 2.2 percent chance of reaching the postseason, which is comparable to the Marlins‘ chances, and less than those of the 63-72 Colorado Rockies. It’s not just their position in the standings that presents a problem; the Yankees aren’t as good as the Red Sox, who have nearly a 100-run edge in run differential over the Bombers. The Adjusted Standings show that the Sox have been nine games better than the Yankees this year. The Red Sox play 20 of their final 29 games at home, where they’ve been a .700 club this season. The Yankees play a slightly tougher schedule down the stretch as well, with just seven games against sub-.500 teams; the Sox have 10 such contests. Finally, the Yankees have just three games left with the Red Sox, the last three games of the season. While they get six cracks at the Rays, at this point the wild-card slot is the target, so games with the Rays are less useful than games against the Red Sox.

Still, the combination of a history of strong finishes, a roster that is loaded with top-tier talent, and perhaps the memory of last September’s surges by the Phillies and Rockies, all leave me unwilling to issue a eulogy for the Yankees’ streak of post-season appearances. It is highly unlikely that the Yankees will catch the Red Sox to win the wild card; it is not impossible, and whether this is stubbornness, fanboyism, or an ugly union of the two, until this team is eliminated or close to it, I’m going to hold back from writing them off.

What has to happen to push the Yankees past the Sox? Well, for starters, they have to win a lot of baseball games. Even a depleted Sox team-J.D. Drew is out, and Josh Beckett is headed to see Dr. James Andrews-can be expected to finish reasonably well. They have a strong lineup core, rotation depth, and a power bullpen. Let’s be unreasonably pessimistic and say that they go 13-13 down the stretch leading up to the last three games of the season. To be in position to sweep the Sox and earn a playoff game, the Yankees would have to go 16-10 in that same period of time. To be in position to take two of three and get that playoff, they’d have to go 18-8, a more daunting task. That has to be the intermediate goal, however: make that last series of the year a meaningful one.

To do that, the Yankees have to score more runs. For all of the talk of how the failure of the Yankees’ young pitchers-who, we’re often reminded, could have been traded for Johan Santana-have been , the Yankees’ run prevention has been fine. The Yanks are seventh in the league in runs allowed, middle of the pack, on pace to allow 748 runs, 29 fewer than they did a season ago, which is a bit more than just the overall decline in scoring would explain.

Let’s chart this, actually

            RS    RA
PECOTA     881   724
Sheehan    891   744
Actual*    793   748

The Yankees’ run prevention has been right in line with expectations. Even though Philip Hughes and Ian Kennedy combined to allow 60 runs in 61 2/3 innings, leaving Darrell Rasner and Sidney Ponson to combine for 100 runs allowed themselves in 162 2/3-folks, that’s more than a quarter of the Yankees runs allowed by four pitchers in less than a fifth of the innings pitched-the Yankees’ overall run prevention has been fine. The development of Jose Veras, Edwar Ramirez, and Joba Chamberlain, along with the comeback year by Mike Mussina, have all cancelled out the back end of the rotation’s failure to be an asset. The Yankees’ pitching is not the reason they’re down to a 1-in-40 shot at October.

No, it’s that other column. The Yankees are going to score 100 fewer runs than expected, and again, that’s not just run context. That’s Robinson Cano and Melky Cabrera failing miserably at developing. That’s Jorge Posada missing 400 PA. That’s Hideki Matsui missing 200 PA. That’s Derek Jeter‘s worst season in a decade. Even Alex Rodriguez’s .307/.395/.581 line, which places him among the league leaders in various advanced metrics, is sullied by his ineffectiveness in high-leverage situations. That’s not a mark against his talent or his character by any means, but his splits show that his production hasn’t impacted games as much as it might-certainly not as much as it did last season. In one of the quirkiest pieces of data of the year, Rodriguez has just three runs batted in, and just one teammate batted in, after the seventh inning this year. Those figures were 31 and 19 a year ago.

The Yankees have scored 641 runs with offensive statistics that could be expected to produce 665; that 24-run shortfall reflects a team-wide failure in high-leverage situations: their performance with runners on base and with runners in scoring position is less than their overall performance by a significant amount. Combined with the failures of their young position players and the critical injury to Posada-itself costing the Yankees 30 runs and three wins, minimum-the lack of high-leverage performance has been part of what looks to be a massive shortfall in runs scored. If the Yankees miss the playoffs, point to the bats, not the arms.

Jorge Posada isn’t walking through that door, so everyone else has to pick up the slack. For the Yankees over the next four weeks, that means Matsui has to be in the lineup and be his walks-‘n-power self. It means Jeter has to put it all together for a month; he’s made contact, drawn walks, hit for power, and had a high BABIP this year, but never more than two of those at any one time. It means the team has to catch some breaks in high-leverage situations, much as they did in yesterday’s game. It means Cano, who even since his brutal April is just at .298/.330/.451, has to put more balls in play, hard, because he has to bat .320 to help the team. It means a random or two-Ivan Rodriguez or Xavier Nady or a recalled Cabrera-is going to have to have an 1100 OPS month.

The Yankees were supposed to average about 5.4 runs per game. If they can pull that trick off for the next 26 games, they can make the last weekend of the season in Boston interesting. Without that kind of offense, though, the streak-13 consecutive postseason appearances-will die, and September 21, 2008, will be the date of the final game at Yankee Stadium.