Like most small-market franchises, the on-court success of the Minnesota Timberwolves hinges on their ability to draft well.

After an aging team built around Kevin Garnett, Latrell Sprewell and Sam Cassell came up short in the 2004 Western Conference Finals, Minnesota had three shots in the lottery from 2005-2007, which they turned into Rashad McCants, Randy Foye and Corey Brewer.

As a result, when they finally traded Garnett, they had almost no talent left on their roster, forcing the franchise to begin another long rebuilding process. The Timberwolves haven’t made the playoffs since 2004, the longest current streak in the NBA.

Building through the draft requires not just projecting which 18-21 year olds can handle the transition to the highest level of basketball in the world but also whether their games will “fit” together over time. It has taken seven long years of wandering through the wilderness, but Minnesota has finally assembled a group of lottery picks with complementary skills.

Ricky Rubio, a pass-first point guard with great floor vision and a mediocre outside shot, is best suited playing with finishers who don’t need to dominate the ball. That description fits two forwards Minnesota drafted with top-four picks, Kevin Love and Derrick Williams, perfectly.

Love, a dominant rebounder with an excellent three-point shot, is the rare 25-point scorer who isn’t a primary offensive option: 59% of his field goal attempts are either assisted or come as the result of an offensive tip-in.

Williams, an athletic forward at 6'9, combined human-highlight reel dunking ability in college with a superb outside shot. And like Love, most of his shots are assisted, although his three-point shoot is still a work in progress, as he’s shooting 27% from beyond the arc as a rookie.

The combination of Williams and Love spreads the floor for Rubio, while Rubio’s penetration creates open looks for his two forwards. Minnesota has one of the most exciting young offenses in the NBA, with Rubio averaging 8.7 assists on only 3.5 turnovers as a 21-year old-rookie.

However, the three don’t mesh as well on the other side of the ball, where neither Rubio, Williams or Love have the necessary length and foot-speed to become elite individual defenders at their respective positions. These deficiencies can be game-planned around, but not when none of their teammates average more than a block a contest.

That’s the most disappointing part of the Timberwolves draft history: despite making seven straight lottery appearances, they didn’t select a defensive-minded big man once.

They took Syracuse point guard Jonny Flynn No. 6 in 2009, the same draft as Rubio, and Syracuse small forward Wesley Johnson No. 3 in 2010.

Flynn has since been dumped to the Houston Rockets, who declined his fourth-year option, while Johnson has struggled to create his own shot, shoot from the perimeter and defend in his time with Minnesota. Even worse, he is already 24-years-old, which doesn’t suggest much room for improvement in his game.

While Williams is a nice piece, they may end up regretting passing on the chance to take Lithuanian teenager Jonas Valanciunas in 2011, an athletic 6’11 big man with a 7’6 wingspan who shoots over 90% from the free-throw line.

The draft is the best place to acquire athletic height, as teams have to overpay significantly for interior defense in free agency. Golden State, a franchise with a young offensive-minded core similar to Minnesota’s, tried to money-whip DeAndre Jordan in the offseason, only to have the Clippers match the offer, forcing them to settle on Kwame Brown at $7 million.

That’s why Kevin McHale’s final mistake as the Timberwolves GM may be his most devastating, as Minnesota has to give up its unprotected first round pick this season as part of the 2005 Sam Cassell-Marko Jaric trade. The 2012 draft is deep with defensive-minded big men, the one piece the Timberwolves need, and they’re locked out of it.

By 2013, with Rubio and Williams in their second seasons in the NBA, it’s unlikely Minnesota will be bad enough to receive a top-10 pick. Their window to improve through the draft is essentially closed.

Nor is trading for a center much of an option, as the rest of the Timberwolves roster is made up of overpaid “mid-level” veterans (Darko Milicic, Luke Ridnour, JJ Barea) or underachieving young players (Johnson, Michael Beasley, Martell Webster, Anthony Randolph).

That leaves free agency, where there are a few intriguing possibilities, but no certainties, in the 2012 class. There’s Greg Oden, Omer Asik, a restricted free agent for the Chicago Bulls, Ian Mahinmi, who has taken over crunch-time minutes at center from Brendan Haywood with Dallas, and Robin Lopez, another restricted free agent who was impressive as a rookie before losing playing time to Marcin Gortat in the last two years.

Franchises that ignore the center position in the draft, particularly small-market ones that can’t attract top-level talent like Dwight Howard and Tyson Chandler, are left to play with fire in free agency.

Minnesota GM David Kahn will need to be either very lucky or very creative to acquire an elite interior defensive presence. The Timberwolves’ future depends on it.