What is basketball’s greatest Finals moment? What two players met in the game’s best duel? What is the greatest dunk of all time? The answers are up to you. From Feb. 15 through March 15, we asked you, the fans, to vote on the greatest plays, moments and players in NBA History. Your answers will be revealed during the "NBA's TOP 10 GREATEST" on The History Channel on April 21 at 8 p.m. ET along with debate and analysis from an expert panel of basketball legends, coaches and sportswriters have to say about it.

Question No. 6: What is the greatest upset in NBA history?

Average Rockets Top Lakers

Despite having just a .500 record in the regular season, the Rockets knock off the Lakers in the West Finals to reach the 1981 Finals.

Bullets Swept by Warriors

The heavily-favored Washington Bullets get swept by the Golden State Warriors in the 1975 Finals.

Celtics Dig Deep Against Lakers

Although Los Angeles' Jerry West was named series MVP, the old and hurting Celtics beat the powerful Lakers in the 1969 Finals.

Knicks Knock Off Heat

In 1999, the eighth-seeded New York Knicks beat the top-seeded Miami Heat in the first round of the playoffs and go all the way to the Finals.

Magic Swept by Rockets

Shaquille O'Neal and the Orlando Magic get swept by the Houston Rockets in the 1995 Finals despite having the best record in the league.

Nineteen in Knick of Time

In 1973, the Knicks would complete the greatest regular-season comeback in NBA history. Down 86-68 with just minutes left against the Bucks, the Knicks would score the last 19 points of the game to pull out the amazing one-point win.

Nuggets Stun Sonics

The Denver Nuggets become the first eighth seed to beat a No. 1 seed by topping the Seattle SuperSonics during the 1994 NBA Playoffs.

Rochester Rocks Mighty Minneapolis

The Rochester Royals surprise the powerful Minneapolis Lakers and win the 1951 Finals.

T-Mac's Thrilling 13 in 35

On Dec. 9, 2004, with the Rockets down 10 with 1:02 left in the game, Tracy McGrady scores 13 points in the final 35 seconds, including a game-winning three-pointer, to lead Houston to an improbable win over the Spurs.

Warriors Stun Spurs

Led by Run-TMC, the seventh-seeded Golden State Warriors beat the second-seeded San Antonio Spurs in the first round of the 1991 playoffs.