There's a scenario in sports that's wilder than a buzzer-beating shot, more crushing than a walk-off home run and so downright preposterous it seldom happens—let alone when there's a major championship on the line. But this week has been different. This week, it's happened twice.

This extraordinary thing we're talking about is a series of unlikely events that only lasts about as long as it takes to pop a champagne cork, but that produces a dramatic 180-degree swing in the outcome. Lots of dramatic finishes come down to one final play. This exotic species requires a combination of two incredible plays—or more.

Monday night in the Stanley Cup Finals, the Chicago Blackhawks trailed the Boston Bruins 2-1 in Game 6 with just 1:16 remaining. Then came the two-play turnaround: Bryan Bickell scored to tie it and 17 seconds later, Dave Bolland scored the winner. The Blackhawks were skating around with the Cup not a minute later.

A week earlier, a similar chain reaction cost the San Antonio Spurs the NBA title. Leading by five with 20 seconds to play in Game 6 of the Finals, the Spurs saw Miami's LeBron James nail a three-pointer to cut the deficit to two, and 15 seconds later, watched Ray Allen kill their celebration with another three. The Heat won the game in overtime and the series two days later.

Here's a collection of memorable two-play title turnabouts.

—Ben Cohen

17 seconds

The Chicago Blackhawks celebrate after winning the Stanley Cup. Getty Images

It took all of 17 seconds for an entire season to end. The Boston Bruins were up 2-1 in Game 6 on Monday night, at home, just 76 seconds of killed clock away from Game 7 on Wednesday. Their probability of winning at that point was about 98%, according to sports statistician Brian Burke, whose model is based on a Poisson scoring distribution and the average number of goals per minute in NHL games. But that was exactly the problem: It also left a 2% chance for the Blackhawks.

15.3 seconds

Michael Jordan sinks the championship winning basket in the 1998 NBA Finals. Reuters

Michael Jordan's last shot in a Chicago Bulls uniform, his game-winner in Game 6 of the 1998 NBA Finals, might be the most famous in NBA history. But it wouldn't have been had Jordan not done something equally magical just 15.3 seconds earlier in stealing the ball from Karl Malone with the Utah Jazz up one. That set the stage for Jordan to dribble down the floor, isolate himself with Byron Russell and drill the dagger, earning himself a sixth NBA title.

36 seconds

David Tyree catches a first-down pass in the fourth quarter in front of safety Rodney Harrison. Getty Images

The game-winning touchdown of Super Bowl XLII is almost an afterthought—all because of "The Helmet Catch." Trailing 14-10 with 1:15 left, New York Giants quarterback Eli Manning somehow eluded a sack, before launching a ball that was hauled in by David Tyree. Four plays and 36 seconds later, Manning connected with Plaxico Burress in the end zone, putting New York in front and spoiling New England's perfect season.

126 seconds

Sergio Aguero scores the winning goal for Manchester City in the 2011-12 season finale. Imago/Zuma Press

The final day of the 2011-12 English Premier League season made the rest of the year look about as action-packed as afternoon tea. Manchester City and Manchester United sat atop the table, with City owning the potential tiebreaker on goal differential. United won to put the pressure on City, which needed a win but found itself losing to Queens Park Rangers in stoppage time. In other words, City was cooked. But then, Edin Dzeko tied the match for City in the 92nd minute and 126 seconds later, Sergio Aguero gave City the lead and its first Premier League championship in more than 40 years.

24 seconds

Tony Womack is congratulated by Luis Gonzalez. Associated Press

The 2001 World Series is still remembered for George W. Bush's first pitch before Game 3 and Derek Jeter's walk-off homer to end Game 4. But the most stunning developments were saved for Game 7. That's when Yankees closer Mariano Rivera coughed up a lead by allowing a one-out double to Arizona infielder Tony Womack, which a 2006 study in the Journal found to be the most clutch hit in baseball history. Two batters later Luis Gonzalez muscled a game-winning bloop single to the outfield. The whole thing happened in just under 24 seconds of game time.