Unless the stars align and the Yankees and Red Sox both make the playoffs this year, this afternoon’s game between the two rival clubs marked the team’s last meeting in Yankee Stadium. As the Yankees did on Wednesday, April 18, 1923, when they opened the House that Ruth Built, New York emerged victorious over Boston for one final time in Yankee Stadium.

Today’s game, in a way, was a vital one not only for the Yankees but for Mike Mussina too. Moose won his 16th game of the year on August 27, and now he won’t win number 17 until at least September. He’s going to have to be nearly perfect to earn himself that elusive 20-win season.

Of course, it didn’t have to be like that today for Mussina, and for that, we again turn to everyone’s favorite punching bag. With two on and one out in the first, A-Rod struck out. With two on and one out in the sixth, A-Rod fouled out to Jason Varitek. Until the seventh, it just seemed, yet again, like one of those games.

But while Mussina would give up his two runs when he hit the Sox’s number eight batter, so too would the Yanks’ bottom of the order come back to haunt Boston. In the seventh, with two outs, Cody Ransom doubled. He’s now 3 for 4 in his short Yankee career. With Jose Molina due up and Hideki Okajima on the mound, Joe Girardi made the right move. While the lefty-lefty matchup didn’t favor the Yanks, Jason Giambi didn’t care, and he launched a ball into center field. Perhaps sitting Giambi against lefties all year hasn’t been the best strategy.

These runs offered the Yankee faithful a glimmer of hope, but in the 8th, when Girardi started to mix and match pitchers, Mussina lost his chance to walk away with a W. He’ll have to win four starts in September to get there.

In the 9th, the Red Sox seemed destined to tempt fate. With Jonathan Papelbon at the ready, they opted to stick with Justin Masterson instead. Masterson allowed a lead-off single to Xavier Nady, and while Robinson Cano failed to advance the runner, a Brett Gardner stolen base — he’s still alive! — pushed the winning run into scoring position. Hideki Matsui was intentionally walked; Pudge Rodriguez was unintentionally walked. And in came Papelbon.

Once again, the fate of the Yankees rested in Jason Giambi’s skilled hands, and he delivered a sharp single into center field. Jason Giambi 3, Boston Red Sox 2. Game over. Yankees win.

In the end, today’s win prevented the more pessimistic among us from driving another nail into the Yankee coffin. They’re six out of the Wild Card with 29 games to play, and they have to outplay both the Red Sox and whichever team doesn’t win the AL Central. They also need to avoid losing to the Blue Jays’ far superior pitchers this weekend.

But for a day, we can forget, to a point, about these travails. In the last meeting between two archrivals in Yankee Stadium, the home team — our home team — won a thrilling game with a walk-off single, and a first-ballot Hall of Fame pitcher — Mariano Rivera — earned the win. Playoffs or not, during a season in which the Yanks would almost rather have their fans forget about the impending demise of Yankee Stadium, during a season in which the team is sending their stadium off with a whimper instead of a roar, today’s storybook game was one for the ages.

There’s no need to declare the Yankee season over that. I’ll let David Pinto’s eloquent eulogy carry the day in that regard.

After all, just a year ago, the Colorado Rockies, the NL’s 2007 World Series representative, were 6.5 games out of the Wild Card. The Yankees are down; they’re not playing well; and Joe Girardi, as David Cone opined on the post-game show tonight, doesn’t really know what to do with this group of ballplayers. But until they’re mathematically eliminated, I’m not ready to throw in the towel. They do, however, have a very steep climb ahead of them.

Tonight, the game started and ended with the Yankee pitching. Sidney Ponson got off to a rocky start in the first inning. Before the Yanks had a chance to bat, they were facing a 2-0 deficit, and Ponson didn’t seem to have that sinker working. But Ponson seemed to right the ship for a few innings, and he pitched through the second, third and fourth without incident.

In the fifth, with the Yanks and Red Sox knotted at two, Ponson allowed another two runs, and Joe Girardi quickly yanked him. Again, a Yankee pitcher couldn’t get out of the fifth, and again the bullpen would be called up on for more than four innings of work.

The bullpen wasn’t up for the job. While Edwar Ramirez and Damaso Marte kept things under control, Jose Veras and David Robertson, once again called upon in a situation in which he was nearly obligated to fail, allowed seven runs in the eighth. That would be all for the Yankees.

Ponson allowed 11 baserunners in 4.2 innings. The bullpen allowed seven earned runs in one inning of work while tossing up zeroes in the other 3.1, and when the game ended, it didn’t matter that A-Rod was 2 for 4 with a run scored and an RBI. It didn’t matter that Jason Giambi blasted yet another home run off Mike Timlin. All that mattered was that Lisfranc injury to Chien-Ming Wang, that reliance on starters that just shouldn’t be here, and an offense that just isn’t doing what it should be doing.

The Yanks are down. But I’m not ready to count them out. Hope springs eternal, even with September growing closer.