Is Ibaka walking through that door?

At this stage for the Oklahoma City Thunder, down 2-0 in the Western Conference finals to the San Antonio Spurs, it's not about what Serge Ibaka can do, it's about what he represents: the unknown.

One week after the Thunder declared Ibaka out for the playoffs, they changed his status to day-to-day.

He hasn't gone through a full practice yet. There's no promise he will before Game 3 on Sunday.

All that's given is hope and possibility.

Maybe, maybe not. Those are terms that are completely comfortable for the Thunder.

Thus far the series has been played in San Antonio's comfort zone. Thunder forward Nick Collison used the perfect description for the Spurs when he called them "organized." The Spurs always seem to be thinking two steps ahead.

The Thunder thrive on the unexpected. For all the criticism of the absence of structure on the court, that hasn't inhibited their success.

Russell Westbrook in particular lives for doing the unexpected. Watching some of the videos in Brian Phillips' Grantland story on Westbrook, in addition to Westbrook's three entries in the top 10 plays of the first round, the recurring theme is how he's so effective by making plays that others wouldn't even attempt.

Point guards aren't supposed to come flying in for weakside blocks or putback dunks. The typical basketball player would simply foul when the game gets late enough that the clock becomes a bigger factor than the deficit. Westbrook goes for the steal -- and got it, against Mike Conley and Chris Paul -- succeeding as much by the element of surprise as his athletic ability.

Now it's Ibaka's turn to be the wild card. Can he play? How effective will he be if he does?

We know how important his presence is to the Thunder's defensive attack. According to data compiled by ESPN Stats & Information, the Spurs are shooting 47 percent in the paint against OKC this season when Ibaka is on the court and 65 percent when he's off it. Are those numbers still relevant?

We also know that the 12 points per game Ibaka averaged in the playoffs are more than the nine total points produced by Collison, Kendrick Perkins and Thabo Sefolosha in the first two games of this series. Could Ibaka maintain that scoring pace against a Spurs defense that's found a way to contest so many Thunder shots?

Danny Green found the right mix of respect for Ibaka's skills and skepticism of his readiness when speaking to reporters Friday: "Obviously [he's] one of the best defensive players in the league, alters everything around the basket, rebounds, and also a floor spreader. He can knock down shots. You've got to respect him, and hopefully if he does come back, he's not as fresh, he's a little rusty when he comes back."

You'll notice that's the first time it's the Spurs' turn to frame things in terms of hope, rather than knowledge. The Spurs also have to start wondering if on an upcoming drive to the basket Ibaka will appear like a decloaked Star Trek spaceship. They also might be a little more reluctant to help defensively if it means leaving Ibaka open for the 15-foot jumper.

Those hints of doubt are more than the Thunder had going for them otherwise.

Yes, they're heading home for the next two games and it was only two years ago that they overcame a 2-0 deficit against the Spurs. But that was with James Harden and a healthy Ibaka. Now they have neither. Just the possibility of a bit of Ibaka.

But it's a welcome uncertainty for Oklahoma City.