After a dominating 20-game stretch, the San Antonio Spurs saw their win streak snapped by the Oklahoma City Thunder on Thursday night in Game 3 of the NBA Western Conference Finals, cutting the Spurs' series lead to 2-1.

The loss was San Antonio's first in almost two months, and it exposed some chinks in the Spurs' previously unbreakable armor. The Thunder will look to even the series on Saturday.

Here are some keys to their Game 4 matchup:

OKC Defense

In beating the Spurs, Oklahoma City held the league's highest-scoring offense to their lowest scoring output (82 points) since Jan. 27, and their lowest field-goal percentage (39.5) since May 7. During San Antonio's impressive run, opponents have failed to slow down the Spurs offense. Disrupting that offense should be the top priority of the Thunder going into this crucial Game 4.

In Game 3, Oklahoma City was able to force 21 Spurs turnovers, with two-thirds of those coming from steals. Those steals can turn into offense quickly and the Thunder's 18 fast-break points in Game 3 contributed greatly to the big win.

Point-Guard Battle

Thunder Coach Scott Brooks' decision to have Thabo Sefolosha guard Tony Parker in Game 3 paid dividends as Sefolosha's length flustered Parker for most of the game. Parker finished with five turnovers and only four assists as the quarterback of San Antonio's attack was out of rhythm.

Parker's counterpart, Russell Westbrook, got his teammates more involved than usual by dishing out nine assists, to go along with only 15 shot attempts. Westbrook had a better all-around game than usual, posting seven rebounds, four steals, and two blocks.

While Parker may be more vital to his team's offense, Westbrook's contributions should not be taken lightly. He has the ability to take over a game, as he did in Game 4 against the Los Angeles Lakers. The athletic guard scored nine straight fourth-quarter points in a thrilling Oklahoma City comeback against L.A.

Sixth Men

While Manu Ginobli has periodically been a major spark off the bench for the Spurs over the years, James Harden appears to be the closest thing to Ginobli, as the left-handed, high-scoring shooting guard is coming off a regular season where he won the Sixth Man of the Year award. Harden plays a similarly aggressive style of basketball as the veteran Argentine. Both players are the primary scorers of their team's second units, and both have had signature fourth quarters in this postseason.

Harden's big night came against the defending-champion Dallas Mavericks in the first round. Dallas, looking to avoid becoming the fifth NBA champion to be swept out of the first round, was up by 10 points at the beginning of the fourth quarter. What followed was pure dominance by Harden, who scored 15 points in the final frame (one fewer than Dallas) leading to a six-point Thunder win.

Ginobli's flash of brilliance came in Game 1 of this series. In a similar performance to Harden's, Ginobli scored 11 points in the fourth quarter to help the Spurs recover from a six-point deficit and escape with the win. Both players will be looking to provide equally bright sparks off the bench, and it will be interesting to see who outplays the other in Game 4.

Home-Court Advantage

Of all the arenas in the league, the one with the most appropriate name has to be Chesapeake Energy Arena. Oklahoma City has embraced this young team with more energy than few other teams in NBA.

This is the Thunder's fourth year in existence following the much-publicized move from Seattle. The city earned an NBA team following its high attendance rates when the New Orleans Hornets relocated in the wake of Hurricane Katrina. The excitement in the city for an NBA team led David Stern to say the NBA had not played its last game in Oklahoma City, after the Hornets had returned home.

Home-court advantage is vital in the NBA, and coming back to Oklahoma City helped energize the young Thunder, leading to their 20-point win on Thursday night. The young team will be leaning on its fans again as it looks to even things up with the veteran Spurs.

Rebounds

So far, these two teams have played to a stalemate when it comes to cleaning up the boards. San Antonio has five more rebounds than Oklahoma City to this point, and all three games have gone to the team who has won the rebounding battle.

The Spurs have been outrebounding the Thunder despite not being able to compete in terms of size. The Thunder frontcourt of Kendrick Perkins, Serge Ibaka, and Nick Collison is much bigger than the Spurs' big-man core of Tim Duncan, Boris Diaw, and Thiago Splitter.

In response to the poor matchup, the Spurs have been relying on Kawhi Leonard, the rookie small forward from San Diego State. The 20-year-old swingman averaged five rebounds per game in the regular season and has continued his stellar play against San Antonio by averaging seven rebounds per game.