There were watershed moments in 1992 inside the Metrodome for a pair of teams that had experienced recent glory.

There was a baseball game on July 29 involving the Oakland A's and the Twins, and there was a football game Oct. 4 involving the Chicago Bears and the Vikings.

The first was the Eric Fox Home Run game. The second was the Jim Harbaugh Audible game.

The Twins were 60-38, leading the AL West by three games and looking like favorites to win a second consecutive World Series when the A's came to Minneapolis for a three-game series. Fox's three-run, pinch-hit home run off Rick Aguilera in the ninth inning gave the A's a 5-4 victory, and a sweep that sent the Twins reeling.

And we mean reeling: not only to a 30-32 finish that left them six games behind the A's, but to eight losing seasons in a row.

The Bears were 2-2 and seeking to re-establish their superiority in the NFC Central when they came to Minneapolis. The Vikings were a revitalized 3-1 under first-year coach Dennis Green, yet the locals were not fully satisfied -- as demonstrated by the boos that accompanied the home team off the field at halftime.

Chicago was leading 13-0 with accurate passing from Harbaugh, strong running from Neal Anderson and fierce defense. That lead went to 20-0 when Harbaugh led a 16-play, 91-yard drive that devoured the opening 10:27 of the second half.

The Bears were not giving the Vikings a breath of life on that afternoon. Mike Ditka's tough guys from a tough-guy town had gone 90-37 over the previous eight seasons -- with seven playoff appearances, six division titles and a Super Bowl victory.

And now the Bears were saying "not so fast" to the critics insisting that the mighty defense had gotten too old, and that Harbaugh remained a mediocre excuse for a quarterback in his third season as the Bears' starter.

The Vikings had punted again after that touchdown and Chicago had a first down at its 33 early in the fourth quarter. The play was to send four receivers deep, put the ball on the Vikings' side of the field, and continue the exit of Purple fans toward the Dome's revolving doors.

Harbaugh went to the line, determined the Vikings secondary was playing soft, and called "80 audible." This made Anderson the primary receiver for a short pass.

"I didn't hear it," Anderson said of the audible.

The running back was caught by surprise when the pass came his way, stumbled, and Vikings safety Todd Scott intercepted and took it 35 yards for a touchdown.

When Harbaugh came to the sideline, Ditka grabbed for his facemask and went into a sideline meltdown. Postgame, Ditka said Harbaugh had been told not to audible because of the noise factor in the Metrodome.

Harbaugh's rationale was this: "He said don't call an audible if the noise is too loud. He left it up to me to determine. ... At that point, I didn't think it was too loud."

Harbaugh was right: By then, one-third of the crowd had left. Ditka was also right: Scott's interception changed the game. The Vikings rallied for a 21-20 victory. Green's Vikings were on the way up; Ditka's Bears were on the way out of contention.

"Sometimes, we're just too smart for our own selves," said Ditka, bitterly, after the game. "When there's a player who knows more than a coach, you've got a problem. If this happens again, there will be definite changes. ... We're not going to put 47 guys' careers in jeopardy for one guy."

In 2011, the 49ers hired Harbaugh away from Stanford as their coach. Early in his tenure, Ditka said:

"He took all that crap I threw at him in Minnesota. If he could handle that, he can handle anything. The 49ers made a great choice. He's going to be a heck of a head coach. He's a strong guy."

Ditka was right about that. He was also right two decades earlier about the audible putting careers in jeopardy.

The Bears finished 5-11 in 1992, and Ditka was fired. Harbaugh lasted one more season, followed by more mediocrity in Indianapolis. The Bears as a whole were 56-88 and reached the playoffs once from 1992 through 2000.

Patrick Reusse can be heard noon-4 weekdays on 1500-AM. preusse@startribune.com