Every year we start to believe that they're too old to contend and every year they prove us wrong.

For the last five years or so, we've been trying to predict the drop-off of the San Antonio Spurs, trying to guess when they would officially be too old to compete. Their superstar coach-player duo of Gregg Popovich and Tim Duncan won their first title together in 1999 and bookended it with their fifth in 2014.

We're in awe of their accomplishments, sure, but we're simply not used to teams staying on top of the league that long, so we naturally try to find the cracks. History has shown us far too many times that egos and contracts get in the way too regularly for a team to reign supreme for years (let alone decades), or at the very least, age tends to wear at least one (if not multiple) of the team's key cogs into the ground.

Not so for these Spurs, however, which are now -- without a doubt -- the biggest post-Jordan dynasty the NBA has seen. 16 seasons with 50-plus wins (17 if you count the pace of the 37-13 lockout-shortened 1998-99 season) since 1997-98. Six Finals appearances. Five rings in a decade and a half. The rÃ©sumÃ© speaks for itself.

Even so, there we were again this year -- as recently as a couple weeks ago -- looking at a declining Spurs team in an improving Western Conference and calling them finished.

The Spurs' annual "Rodeo Trip" has often been a marker in the past for when the team really gelled and made their definitive case for title contention. This year, they had arguably their worst trip in the Pop-Duncan era, going 2-5 during their first seven games away from San Antonio, topped off by a four-game losing streak culminating on February 25th. At that point in the season, they were the 7 seed in the Western Conference, clinging on to a two-game lead over the 8 seed, the Oklahoma City Thunder. Their Offensive Rating of 103.5 (13th), Defensive Rating of 100.4 (7th), and Net Rating of +3.1 (10th) still placed them in the league's "best" but no longer made them seem like part of the "elite".

Then, with two games left on said "Rodeo Trip," the Spurs flipped that switch, the same as they always have. Over the last six games (all Spurs wins), San Antonio has looked just as strong and well-oiled as they ever have. They've beaten their opponents by an average of 15.8 points per game. Their Offensive Rating of 112.6 (1st), Defensive Rating of 95.5 (6th), and Net Rating of +17.1 (2nd) during that span makes them look like the elite, dominant team of old.

Tim Duncan, at 38 years old, has been having an amazing season, averaging 14.1 points, 9.6 rebounds, 2.8 assists, 0.8 steals, and 1.8 blocks per game, while shooting 49.2% from the field and 71.4% from the free throw line. It's not quite the 20/10 days of old, but it's pretty damn close.

Over these last six games, however, the Big Fundamental has averaged only 8.8 points, 7.7 rebounds, and 1.7 blocks per contest, while shooting an uncharacteristic 39.2% from the floor and 59.1% from the charity stripe. He even went his first full game without scoring a single field goal in his 18-year career on Sunday, ending a record-setting 1,311-game streak. Despite that, Duncan's Spurs still beat the Chicago Bulls by 11 points. Something does not compute.

Kawhi Leonard has been playing inspired ball as of late, reminding us why he won Finals MVP honors last year, with averages of 21.5 points, 8.2 rebounds, 1.8 assists, 2.7 steals, 1.5 blocks, 54.5% shooting from the field, and 85.0% shooting from the line during this six-game winning streak. Even so, it remains obvious that it is still one of San Antonio's elder statesmen that is the deciding factor in how well the Spurs manage to perform.

Manu Ginobili has been turning back the clock himself, but it seems the Spurs can only go as far as Tony Parker takes them this season. The Spurs are 7-7 without Parker this year compared to 33-16 when he suits up. Now, just take a look at the difference in Parker's numbers in those wins, compared to in those 16 losses.

Tony Parker PTS FG% 3P% FT% REB AST TOV 33 Wins 16.9 50.0% 53.1% 81.3% 2.0 5.0 2.2 16 Losses 9.9 39.3% 34.8% 79.2% 1.8 4.7 2.4

It seems that as Tony Parker goes, the Spurs will follow. There's perhaps no better proof of that than this six game winning streak, during which Parker has averaged 20.5 points, 2.5 rebounds, 4.5 assists, 1.2 steals, and 0.7 turnovers per contest, while shooting 51.5% from the field. During the four-game losing streak that immediately preceded the current winning patch, for contrast, Parker scored 7.5 points per game while shooting 28.9% from the field. The Spurs have proven that they can cover for Duncan, Ginobili, and Kawhi when they struggle, but they've almost never gotten it done without a strong performance from Parker. Now, Tony's revitalized and so too are the Spurs' title chances (we currently have them ninth at 3.1%).

So, here we are. After spending almost the entire season to date in the 7 seed, the Spurs have climbed to the 6 seed and are tied in the loss column (23) with the fifth-place Clippers. They also sit only 2.0 games behind the fourth-place Blazers and only 3.0 behind the third-place Rockets. They might not catch the Southwest Division-leading Grizzlies (5.0 games back), but they're making a play for homecourt advantage in the first round. Even if they stick in the bottom half of the bracket, no one at the top will want the Spurs as a 6, 7, or 8 seed when they're playing like this.

No matter how many times we count them out, the Spurs continue to prove us wrong. Maybe we'll learn next year.