Someone call Deer Park, Texas, and check on Andy Pettitte, because right now, the Core Four is shaking on its foundation.
On a day on which it was never more obvious that a changing of the old guard is in progress, the Yankees lost a game, and a series, to the Red Sox on Sunday night under circumstances which, in years gone by, they almost surely would have won.
And the most crushing blow of all was they were just three outs, just one average Rivera inning, away from taking two of three from the Red Sox and leaving Boston a game ahead in the AL East.
Freddy Garcia had pitched a masterful five innings, holding the Red Sox to one run and five hits, and the Yankees had dodged a bullet in the sixth when Boone Logan and Cory Wade combined to strand two runners with one out.
But it took nine pitches for Mo to blow a one-run lead in the bottom of the ninth, and 13 pitches for Phil Hughes, in his newly minted role as emergency reliever, to undo all the good that five previous Yankees pitchers had done in holding the powerful Red Sox lineup at bay, at least until Rivera came in.
The final score, 3-2 Red Sox, was both evidence of how well the Yankees had pitched most of the night and how quickly, and stunningly, things turned around for them.
It is always a surprise, of course, when Rivera blows a save -- he had not given one up since July 3 against the Mets at Citi Field -- but having blown four previously this year and now 14 in his career to the Red Sox, nearly twice as many as he has to any other team, this certainly was not a shock.
But what is a shock is how quickly the solid base of this team has eroded, and even though it has been a long, gradual process, the events of Sunday only served to reinforce the knowledge that all glory, no matter how well-established, is fleeting.
Before the game, Posada, who will turn 40 on Aug. 17, was told by Joe Girardi that his services as a designated hitter will no longer be desired, at least until further notice.
And about eight hours later -- the game lasted a nearly intolerable four hours, 15 minutes -- Rivera received an almost equally disturbing message from the Red Sox bats.
"It's a loss," Rivera said when asked if there were greater significance to this one because of who it came against and under what circumstances. "A loss is a loss. It don't matter how you look at it. And the only one to blame is myself. I didn't get it done."
By the numbers, Rivera has had an outstanding season -- 29 saves, a 1.87 ERA and a .232 opponents' batting average -- but he had a scare around the All-Star break with some soreness in his right triceps that cost him a couple of games, and there have been a couple of near-blown saves to go along with the five official ones, which matches his total for all of 2010 and is the most he's had since 2003.
Sooner or later, his magic will come to an end, as all things do.
So, too, will Jeter's. He has had his magical moment for this season, the transcendent five-hit day that vaulted him over the 3,000-hit threshold, and lately he has hit the ball better than he has since the first half of last season, his average up to .273.
But the days when you feared Jeter in the situation he came up in last night -- game tied, runner on second and one out in the top of the ninth -- are long over, and it was hardly a surprise when Jeter tapped out to third. And even with his improvement, his percentage of ground balls is about the same as it was last year (65 percent), when he hit more of them than anyone in baseball.
Even with his five-hit explosion on July 9 at Yankee Stadium, and another Wednesday in Chicago, the player Jeter was last year is essentially the player he remains this year. And that player bears little resemblance to the one who was an integral part of five World Series championship teams.
Which brings us to Posada, who back in May had been told by Girardi he would no longer be his regular DH against left-handed pitching. Sunday afternoon, Girardi told Posada the same thing against right-handed pitching. Since Posada no longer catches and the Yankees rarely pinch hit, his opportunities to play much the remainder of the season -- the last of what is almost certainly his final Yankees contract -- will be severely limited.
Sunday night, it was Gardner and Eduardo Nunez, two of the smallest Yankees and among the least likely to be called Bronx Bombers, who provided the firepower against the Red Sox. Nunez deposited a Josh Beckett cutter into the seats above the Green Monster in the fifth inning to tie the game at 1, and Gardner absolutely crushed a Matt Albers serving over the Red Sox bullpen, only his fifth home run of the year and first since June 19, to give the Yankees a 2-1 lead in the seventh.
But Marco Scutaro, who has tormented Rivera in the past, banged a cutter high off the Monster, and indeed, when it left the bat, it looked as if it might leave the park. After a sacrifice bunt by Jacoby Ellsbury, Dustin Pedroia lined Mo's second pitch deep enough into the left-field corner that Scutaro easily scored the tying run. "It wasn't in the place I wanted it to be," Rivera said. "It was a little down, it should have really been up. But you can't do nothing about it. That's baseball."
By the time Hughes came in to face the heart of the Red Sox order -- Kevin Youkilis, David Ortiz and Carl Crawford in the bottom of the 10th -- an air of inevitability seemed to hang over the prospect, unthinkable an inning before, of a Yankees defeat.
And sure enough, with one out, Ortiz doubled into the right-field corner, and after a pep talk from Girardi and an intentional walk to Crawford, Josh Reddick, a rookie who had thrown out Russell Martin trying to stretch a single in a key fifth-inning play, lined Hughes' first pitch, a flat curveball, into left field for the game-winning hit.
"To be so close to taking two out of three, and then lose, it's kind of a hit," Hughes said. "I've got to do a better job in those situations."
Hughes, of course, will have plenty more time to make up for his gaffe. For Posada, Rivera and Jeter, the opportunities dwindle as the days move on.
The Yankees lost a big game and an even bigger series Sunday night, but those are nothing compared to what this team is poised to lose over the next couple of years.