Kareem Abdul-Jabbar and Magic Johnson. Larry Bird and Kevin McHale. Michael Jordan and Scottie Pippen. John Stockton and Karl Malone. Kobe Bryant and Shaquille O'Neal. These are just some of the greatest duos to have ever graced the basketball court. Most fans have fond memories of the respective historic partnerships of these pairings, and as such, have become part of NBA history for now and forever.

On the other side of the spectrum, however, there have been more than a few NBA duos that you've probably either completely forgotten about or never even knew existed. This may be because of one reason or another, but what is undeniable is that the pairings we have below could have easily been part of our all-time greats list had their respective circumstances been more favorable.

5. Tim Duncan and Tracy McGrady

We all know how Tim Duncan is perhaps the greatest San Antonio Spurs player of all time. However, do you remember the time that Tracy McGrady joined him in San Antonio?

Tim Duncan, Spurs

Well, technically speaking, this was already at the very tail end of McGrady's career. He was never really able to contribute much for the Spurs, serving as a bench player who logged no more than 10 minutes per contest on average. His production rate was a far cry from his All-Star self, but for what it's worth, with the Spurs going all the way to the Finals during the 2012-13 season, this was the first time in McGrady's decorated career that he ever went past the first round in the playoffs.

McGrady played for barely a season in San Antonio and ended up calling it a career at the end of the campaign.

4. Charles Barkley and Moses Malone

Did you know that the Charles Barkley once played alongside the great Moses Malone? These two joined forces with the Philadelphia 76ers at the onset of Barkley's career.

Sixers-Charles-Barkley

Malone was already a bona fide superstar at that point, having led the Sixers to the NBA championship in 1983 while also bagging MVP honors for the season. In 1984, Philly drafted Barkley fifth overall, and the short-lived partnership between these two began.

Barkley made an instant impact upon his arrival. He got so good that the Sixers opted to trade away Malone a couple of years later. Malone was already 31 at that time and was on the decline. Philadelphia decided to cash in on him, with the focus now resting on Barkley as the franchise's new cornerstone superstar of the future.

3. Shaquille O'Neal and LeBron James

Shaquille O'Neal and LeBron James are two of the very best NBA players of all time. This is exactly why it's amazing to think that the careers of these two once intersected. The timing, however, could have been better.

NBA, Shaquille O'Neal, Shaq

Shaq was already 37 when he signed with the Cleveland Cavaliers. O'Neal spent only one season with the Cavs during the 2009-10 season, and it's safe to say that he was already a shadow of his former self.

Despite O'Neal's presence, the Cavs were eliminated in the second round of the playoffs courtesy of the Boston Celitcs. Incidentally, that turned out to be LeBron's final season of his first stint with the Cavs, as he decided to take his talents to South Beach at the end of another disappointing campaign in Cleveland.

2. Michael Jordan and George Gervin

Scottie Pippen is easily Michael Jordan's greatest partner-in-crime of all time. As a matter of fact, many consider this pair to be the greatest NBA duo in the history of the sport. There was a time, however, that MJ actually had the opportunity to play with the legendary George Gervin.

Michael Jordan, Bulls, NBA

The Iceman joined the Chicago Bulls in 1985 in what was Jordan's second year in the league. Gervin was coming off yet another All-Star year in San Antonio, and the general belief was that he could help a young and promising Bulls side take the next step, while also taking Jordan under his wing.

While their single season together may have had an influence in Jordan's career moving forward, it resulted in a first-round exit for the Bulls in the 1986 playoffs. Gervin called it a career at the end of that season.

1. Kobe Bryant and Steve Nash

Most folks will probably remember the Kobe Bryant-Steve Nash pairing with the Los Angeles Lakers. Nevertheless, this still makes it to the top of our list for the mere fact that this could have become an all-time great backcourt pairing — if only things fell into place.

Steve Nash, Kobe Bryant, Lakers

Once fierce competitors in the West, these two teamed up in 2012 when Nash joined the Lakers. Despite being 38 at that time, Nash was still coming off an All-Star year, so there was at least some hope that a pairing with Kobe in Hollywood would produce fireworks, especially with Dwight Howard also around. Remember that Sports Illustrated cover?

It did anything but that, however, with the Lakers getting eliminated in the first round during the 2013 playoffs. Nash was plagued with injuries the following year, playing just 15 games in what turned out to be the final season of his career. Los Angeles didn't even make it to the playoffs that year, with Bryant also missing virtually the entire campaign with a torn Achilles.