3 key questions for Thunder-Spurs series

Having both cruised past their first-round battles virtually unscathed, the real test has arrived for the Oklahoma City Thunder and the San Antonio Spurs.

Two of the top four teams in the league are set to square off in what's widely expected to be the most hotly contested semifinals series in either conference.

Here's three questions to be answered.

Who does Kawhi guard?

The hardest thing about having a player like Kawhi Leonard is deciding who he should guard, or rather, who he should shut down.

Leonard, a two-time reigning Defensive Player of the Year, has the rare ability to smother either Kevin Durant or Russell Westbrook. But who do you stop - the league's most physically overwhelming ball-handler in Westbrook, or a deadly finisher like Durant?

Siccing Leonard on Westbrook would be tempting. Leonard is by far the Spurs' most athletic wing, and having Leonard guard Westbrook's thundering pick-and-rolls could keep the number of help defenders to a minimum. If Leonard could single-handedly keep Westbrook out of the paint, the Thunder would have no one to set the table on offense.

Chances are Popovich pits Leonard against Durant. The Durantula is a walking matchup nightmare, but he really doesn't have a concerted advantage against The Claw. Leonard has the strength to body up, the speed to hound Durant around screens, the discipline to stay back on Durant's crossovers, and the length to contest the shot.

Most of all, pitting Leonard against Durant would allow Danny Green to chase Westbrook, rather than the other way around. That way there would be fewer mismatches, but regardless, expect plenty of ball screens between Westbrook and Durant to switch it up.

Can Donovan keep up with Pop?

A big hullabaloo was made when Billy Donovan succeeded Scott Brooks on the sidelines. Scott was supposedly to blame for a backward offense that relied heavily on its star players to conjure magic out of thin air.

Except, that very same trend carried out under Donovan. He's added a few wrinkles to their game, but nothing that's ultimately game-changing. The Thunder's best players remain mind-numbingly simple. Like Brooks before him, Donovan has been blamed for the Thunder's predictable sets in crunch time, and he's been criticized for being slow to adjust.

So it's fair to ask: How would Donovan match up against a chess master like Popovich?

Look for Popovich to have his players drilled strictly on what sets to run and what priorities are to be followed on defense. The Spurs are founded on "good execution" (Westbrook would approve) and it's on Donovan to see the whole board, rather than relying entirely on his stars to produce brilliance time and time again.

Will the Spurs' superior depth matter?

The Spurs romped opponents this season because they were able to maintain a high quality of play for the full 48 minutes.

Their starters outscored opponents by 6.7 points per game, then their bench paced their counterparts by another 3.9 points. No other team in the league came close to matching the Spurs in terms of quality bench players, especially since the Thunder's top two backup options are a defensively inept center in Enes Kanter and a thoroughly ineffectual wing in Randy Foye.

At the same time, the Thunder unquestionably boast more high-end talent in the starting unit, and if Donovan uses his timeouts wisely, he could play the trio of Westbrook, Durant, and Serge Ibaka nearly the entire game. That would render the Spurs' bench advantage nearly superfluous.

That being said, if San Antonio's bench could buy its starters some time throughout the middle quarters, that could keep the Spurs fresh for crunch time. On the other side of the coin, riding Durant and Westbrook for 45 minutes a night could leave them further exposed down the stretch where they've already struggled to close out games.