Entering the season, the Oklahoma City Thunder were the championship favorites in most people's books. They had brought back essentially their entire team from their remarkable run last season, and the continued growth of their core left much room for optimism.
That optimism hasn't entirely faded. But there is now reason for doubt.
After starting the season with a ridiculous, 24-1 record, the Thunder have since slipped. They hold a 42-14 record as they exit the All-Star break. Although they still possess the one-seed in the Western Conference, the San Antonio Spurs are hot on their tails.
But their competition in the Western Conference has been documented at length. What's truly concerning is the rapid rise of certain contenders in the East.
Heading into the season, it was widely expected that no team from the East would truly be able to rival the Western Conference champion in the NBA Finals. The Detroit Pistons (and a small number of other Eastern Conference teams), are slowly proving this assumption wrong.
It signifies a new landscape for the new Thunder, and it's perhaps the season's most concerning development.
The Pistons are starting to look like a real championship threat. That's a scary thought.
Repeating as champions is the hardest thing to do in the NBA. Taking that for granted in the first place is a serious mistake.
Both the Nuggets and the Spurs have the talent and the cohesion to challenge Oklahoma City. While San Antonio's rapid ascension comes as a bit of a surprise, stiff in-conference competition should not. The Thunder have a target on their backs. It's the reality of being reigning champions.
What does come as a surprise, however, is how rapidly Detroit has established themselves as contenders. They currently hold the NBA's best winning percentage at 40-13. They have the second-best net rating in the league, trailing only Oklahoma City.
They are absolutely formidable defensively, and there's a real chance the Thunder see them in the NBA Finals if they are able to return there. The threats in the East don't stop there, however.
Both the New York Knicks and the Cleveland Cavaliers have found their stride recently. Cleveland possesses the best offense in the NBA over the past month, while the Knicks possess the best defense and the best net rating.
If either of these teams got hot at the right time, they could present hefty challenges in a hypothetical Finals matchup.
It appears the Thunder have more on their plate than just the Nuggets and the Spurs. In a year where the East was supposed to be "wide open", a set of teams have emerged who could be serious threats.
With the way Oklahoma City has played recently, the timing couldn't be worse.