One trend has become very apparent since the NBA expanded each round of its playoffs to best-of-seven game affairs; it's awfully tough for lower seeds - underdogs - to win a series, let alone a conference title. Best-of-seven series have greatly reduced the chances of upsets. First-round NBA series used to be best-of-three, then best-of-five, and underdogs had a much better chance of taking two out of three games or three out of five from a better team. But four out of seven? Not so much.

That all being said, we wonder if there any betting value in backing some of the longer shots on this season's NBA playoffs futures boards.

Longer Series, Fewer Shockers

Most of the greatest NBA playoff series upsets of all-time came in shorter series.

The eighth-seeded Denver Nuggets' upset of the top-seeded Seattle Supersonics in the first round of the 1994 NBA playoffs is thought by many to be the greatest series shocker in NBA playoff history. But that came in just a five-game series.

In 1984 the New Jersey Nets, a six seed, upset Dr. J, Moses Malone and their defending league champion Philadelphia 76ers in the first round. That also was a five-game series.

And in 1999 the eighth-seeded New York Knicks upset the top-seeded Miami Heat in the first-round; but that also was a five-game series.

From our memory the biggest NBA playoff upset since all series went to seven games is probably eighth-seeded Golden State's victory over top-seeded Dallas in 2007.

The cream always seems to rise to the top in the NBA playoffs, and while some might say that produces "true" champions, others (including your humble narrator) lament the fact that underdogs win so few series and championships, because it deprives NBA futures bettors of potential big payouts, or at least of some value on playoff futures boards.

Here's our best guess as to the best value on potential NBA "Cinderellas" for this playoff season.

In the East

The eighth-seeded Atlanta Hawks took the first game of their first-round series with the top-seeded Indiana Pacers, and suddenly it's not inconceivable an eight seed could advance, especially considering how Indiana has been playing the last month or so.

If Atlanta could get past the Pacers it might then meet up with fifth-seeded Washington, which has taken the first two games of its series with the Bulls on the road. The Hawks lost the season series to the Wizards three games to one, but Atlanta was within a bucket in the fourth quarter in two of those losses.

Looking down the road a bit, the Hawks split their season series with Miami 2-2, and one of their losses came in overtime.

Washington now heads home to host Chicago for Games 3 and 4. If the Wiz can finish off the Bulls they'll then meet either a floundering Indiana team or the Hawks. Washington ended the season on an 8-3 run, which included a 91-78 victory over the Pacers.

As of early this week Bovada was offering the Wizards at 25/1, Atlanta at 150/1 on its updated Eastern Conference championship futures board.

In the West

The Memphis Grizzlies won 50 games this season, but all it got them was a seven seed and a first-round date with Oklahoma City. But the Grizzlies split the first two games in OKC and now own home-court advantage, which is nice considering Memphis has won its last 14 in a row at the Grindhouse.

If the Grizz can get by the Thunder, they would run into either the LA Clippers or Golden State. Memphis took the season series from LA two games to one and split four games with the Warriors.

The fifth-seeded Portland Trailblazers, powered by Texas native LaMarcus Aldridge, won 54 games this season and have taken the first two games of their playoff series with the Rockets on the road. Portland ended the regular season with a five-game winning streak, and overall has won 11 of its last 12.

If the Blazers can finish off Houston, they'll run into either top-seeded San Antonio or eighth-seeded Dallas, who have split the first two games of their first-round series. Portland split four games with the Spurs this season, and while the Blazers dropped two of three games to the Mavs, those two losses came by a total of seven points.

As of earlier this week Bovada was offering Portland at 10/1, Memphis at 28/1 on its updated Western Conference betting board.