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The series between the San Antonio Spurs and Dallas Mavericks was supposed to be among the easiest to predict in the NBA playoffs' first round.

So much for that.

After the Spurs narrowly escaped with a 93-89 win in a topsy-turvy Game 4 that looked to be over a half-dozen times, these two Texas titans head into Game 5 with the series all knotted up at two games apiece.

Monday night's thriller swung violently back and forth, featuring inspired runs from both teams and ending, appropriately, with a critical last-second shot trickling out. It wasn't supposed to be like this—not in Game 4 and not in the series as a whole.

The Spurs were supposed to walk over the Mavs, but the only blowout in the series belongs to Dallas, a 113-92 thumping in Game 2.

Suffice it to say, we've got a series on our hands.

So, who's got the edge moving forward?

The Smart Money?

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The regular season actually counts for something, right?

If it does, the safe bet is still on the Spurs. They were the superior team all year long, whereas Dallas has long been viewed as a fun, well-coached but ultimately flawed club. San Antonio has simply profiled as the better, more complete team from the moment the 2013-14 campaign tipped off.

Mavericks' and Spurs' Regular-Season Stats ORtg DRtg Net Rating Record San Antonio Spurs 108.2 100.1 +8.1 62-20 Dallas Mavericks 109.0 105.9 +3.1 49-33 NBA.com

Plus, the matchups in this series figured to favor the Spurs. Dallas wasn't supposed to be able to disrupt San Antonio's ultra-efficient attack, and most thought the combination of Monta Ellis and Jose Calderon would provide about as much resistance against Tony Parker's drives as wet tissue paper.

The Spurs were and, theoretically, still are the more balanced team. That much was apparent in the way they built a 20-point advantage in Game 4. But then again, the Mavs erased that advantage and took the contest down to the wire.

So you still might want to hedge whatever "smart money" you've wagered on the Spurs.

In looking at the way this series has played out so far, it bears mentioning the current 2-2 tie isn't all that far from being a 3-1 advantage for San Antonio. Were it not for Vince Carter's fall-away game-winner from the left corner in Game 3, Monday's result would have pushed Dallas to the brink of elimination.

And there's no way Game 4 would have been nearly as close as it was without DeJuan Blair turning in the "Where did that come from?" line of the postseason, pummeling the Spurs for 12 points and 11 rebounds (five on the offensive end) in just 16 minutes.

Dallas isn't exactly lucky to be tied in this series, but it has gotten a couple of key breaks.

Better than We Thought

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Let's not spend too much time dwelling on the good fortune that has Dallas tied up with San Antonio. The truth is, Rick Carlisle's Mavs have earned their split by making extremely shrewd adjustments.

Those tweaks have countered many of San Antonio's built-in advantages in ways nobody foresaw, per Zach Lowe of Grantland:

The most shocking series so far. The Mavs have junked things up on defense, slotting Shawn Marion on Tony Parker, hiding Jose Calderon on Danny Green, and switching a lot of pick-and-rolls. Those switches carry a cost — Parker dribbling around against big men — but they have gummed up the Spurs’ beautiful game.

It's not often you see a coaching matchup involving Gregg Popovich played to a draw through four games, but that's how good Carlisle has been. Fear not, though; Carlisle will never measure up to Popovich's standard of delightful press conference surliness:

In that regard, Pop remains peerless.

Beyond Carlisle's brilliance, the Mavs also have Dirk Nowitzki, a man whose singular offensive genius creates the opportunity for a good shot in even the most broken, seemingly doomed possessions. He buried an exemplary jumper from the left wing after terminating his dribble in the fourth quarter of Game 4.

As long as he's around, Dallas will always have a chance to score the ball.

And let's not forget Ellis, who wasn't efficient on Monday (6-of-20 from the field with four turnovers) but is still a uniquely athletic threat who can worm his way into the lane at will.

He's also a good example of how the luck that won Dallas Game 3 cuts both ways.

The lefty layup he missed on the Mavs' final offensive possession is one he's made countless times before. It was a tough finish, requiring the dexterity to locate the rim off a high-velocity spin and the body control to finish in traffic, but Ellis completes plays like that all the time.

The Spurs dodged a bullet when his game-tying attempt just refused to drop.

So, Who Ya Got?

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It's scary to point to the larger sample of regular-season data and ignore the recent developments between two seemingly equal foes. That's exactly the kind of thinking that is about to make a whole lot of observers (yours truly included) very wrong about the outcome of the series between the Indiana Pacers and Atlanta Hawks.

But the Spurs are just too experienced, too talented and too high-functioning in all facets of the game to give this series away.

Sure, they've got to take better care of the rock, and they've got to adjust to the way Carlisle is matching up with bigger wings on Parker. But those are things San Antonio has faced before. There's nothing new to this team.

Plus, the Spurs' regular-season dominance affords them home-court advantage. Here, that means another two games at home to Dallas' one. So even if San Antonio splits the next two, it'll head home for a decisive Game 7.

In a series this tight, that could make all the difference.

Dallas is still flawed. And though it has put up a far better fight than anybody expected, there's still a sense that Carlisle is doing this with smoke and mirrors.

San Antonio is a legitimate champion. It's something different than Dallas.

As such, it's just too hard to imagine the Spurs failing to make the necessary adjustments.

We'll give San Antonio the edge going forward, but the fact that we're even having a debate on the subject says a ton about Dallas' surprising quality—and the historically entertaining nature of this first round.

In that sense, it's really us viewers who have the biggest advantage.