Basic Trope: If they're the underdog in the Big Game, they'll win.
Straight: The Trope High Wildcats are the underdog going into the big championship game against the Opposing Sports Team, but thanks to mix of heart and luck, they pull out the win.
Exaggerated: The Wildcats are underdogs in every game they play, and often by large point margins. They win them all in a blowout.
The Wildcats are decent enough to reasonably expect to get into the final, but that final is against their better-funded, professionally-coached rivals who've always wiped the floor with them in the past.
The Wildcats don't actually win, but they do manage to draw the game with the top-dog team, gaining a great deal of respect in the process.
Just because they're not favored in the stat line doesn't automatically mean they'll lose.
The other team got overconfident and screwed up, allowing the Wildcats to win.
The pregame stat line dictates everything about Wildcats' games - if they say they're favored by 4 points, they win by exactly that amount.
Subverted: A second-half comeback brings it right Down to the Last Play - but the Wildcats player blows it. Wildcats lose.
...But wait! It was revealed that the Opposing Sports Team was cheating, and the Wildcats get one more chance to make the play - which they do. Wildcats win!
The Wildcats are awarded a victory on pity.
To invoke the trope, every team in the league tries to claim they're the underdogs, even the teams who have been winning for decades.
Because of this trope, the sports bookies flip the table when it comes to betting - a bet on the favored team actually pays out more
It comes down to the last play, but the Wildcats player is unable to make it. Then it's revealed the other team was cheating, and the Wildcats make the second chance...then that ruling is overturned when it's revealed the other team wasn't cheating.
The reason the Wildcats are seen as underdogs is because they're hopelessly inconsistent. When things go their way they can be incredibly competent, but when they don't, they fall apart.
Averted: Sometimes underdogs lose, sometimes they pull an upset.