SAN ANTONIO — It's a matchup that seemed destined for later in the playoffs.

But in the hyper-competitive Western Conference, the third-seeded San Antonio Spurs and sixth-seeded Phoenix Suns will renew their rivalry in a first-round matchup.

Last year, many thought their heated second-round series was the real finals. The Spurs won in six games on their way to a fourth NBA championship.

"It's a heck of a matchup. It's a big challenge for us," Spurs coach Gregg Popovich said. "We've got to try to figure something out. They're obviously a team that can win the whole deal, and we got them in the first round."

Even though it's earlier this postseason, their series that starts today in San Antonio could be the best of the first round, for one big — really big — reason.

The run-and-gun Suns acquired Shaquille O'Neal in a blockbuster midseason trade. With the aging 7-foot-1 superstar on the roster, they'll be looking to boost their defense against the defending champions.

"They have both things there. They can go small and run it a little bit more or they can slow it down and go big," Spurs star Tim Duncan said. "It gives them a different dynamic on both ends and obviously makes them a better team."

Duncan was sure to add: "Luckily enough I think we can do both, too. We can push the ball against them, we can slow it down."

The Suns beat the Spurs both times they played after O'Neal came on board. That included a 96-79 thumping in San Antonio a little more than a week ago. The Spurs allow 90.5 points a game, the fewest in the West.

The Spurs are on a quest for back-to-back titles, something they weren't able to do after they won championships in 1999, 2003 and 2005.