The Oklahoma City Thunder very well might be the surprise of the NBA playoffs --not so much in the fact that they beat the Spurs to advance to the Western Conference Finals, but in how dominant they were doing it.

Still, for the hype surrounding Kevin Durant, Russell Westbrook and Co., here's the simple truth: They're still overwhelming underdogs heading into the Western Conference Finals against the Golden State Warriors. Odds were released following Thursday night's win, and it isn't pretty for OKC fans.

According to Jeff Sherman of the Westgate Super Book, the Warriors opened as eight-point favorites in Game 1, and had 5-1 odds to win the series overall.

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NBA Western Conference Finals

Game 1

OKC Thunder 231
GS Warriors -8

Series Price
Thunder +400
Warriors -500

— Jeff Sherman (@golfodds) May 13, 2016

The opening line for Game 1 has since dropped, but not by much.

NBA Western Conference Finals

Game 1

OKC Thunder 223.5
GS Warriors -7.5

Series Price
Thunder +400
Warriors -500

— Jeff Sherman (@golfodds) May 13, 2016

Quickly browsing the internet shows that the Westgate's odds are pretty in line with everyone else's, as BetOnline has the Warriors opening as a 7.5 point favorite, and Vegas Insider has them as a full 10-point favorite.

It's been an incredible run for the Thunder.

But if Vegas is any indicator, it could quickly -- and ugly -- for Oklahoma City.