Imagine being one of your favourite team's most fervent fans and ruining their chances of sporting glory.
That's exactly what hapless Chicago Cubs supporter Steve Bartman did with his heroes on the verge of their first World Series since 1945.
With the Cubs 3-2 up in their best-of-seven series against Florida for the National League title, and 3-0 ahead in game six, their return to baseball's Fall Classic was seemingly assured.
But then, with Chicago five outs away from the NL championship, came Mr Bartman's intervention.
As he rose to try to catch an eighth-inning Marlins foul fly-ball dropping towards him, he didn't notice Cubs star Moises Alou leaping to do the same.
Bartman got in Alou's way and the rest, as they say, is history.
Florida celebrated their let-off by hitting eight runs to level the series, and won again in Chicago the next night to book their berth in the season's finale.
OK, so it may not be entirely fair to blame Bartman for the Cubs' woes, but sports fans needs a scapegoat when things go wrong.
JFK: "I'm innocent," claims Bartman
So one minute you're an unassuming little league baseball coach from the suburbs, and the next you're the Windy City's biggest Public Enemy Number One since Al Capone.
His fellow fans showed their ire with signs at the Cub's Wrigley Field calling Bartman "America's Most Wanted" and worse.
The Governor of Illinois described his actions as "stupid" and one city councillor suggested he should move - to Alaska.
Mocked-up images on the internet blamed Bartman for everything from JFK's assassination to the Hindenburg airship disaster.
But it wasn't all bad news for the 26-year-old.
Fans of the Cub's local rivals the Chicago White Sox rang radio phone-ins offering him safe-house protection in the city.
Jeb Bush, the Governor of Florida and brother of US president George W, said Bartman could apply for political asylum in the Sunshine State.
Govenor Bush extended a warm Florida welcome to Bartman
And grateful Marlins fans offered him everything from free plastic surgery and lifetime membership of a strip club to an all-expenses paid holiday.
Of course, all Bartman really wanted was for his beloved Cubs to win.
"I am so truly sorry from the bottom of this Cubs fan's broken heart," he said in a statement.
And he didn't even get to keep the ball as a souvenir...