Dikembe Mutombo (left) got the best of Shawn Kemp in the 1994 playoffs. (Andrew D. Bernstein/NBAE via Getty Images)

The Hawks lead the Pacers 3-2 and have a chance to close out the Eastern Conference first-round series on Thursday in Atlanta.

If the 38-win Hawks complete the upset of the 56-win Pacers, they would become the sixth No. 8 seed to beat a No. 1 seed since the NBA expanded to a 16-team playoff format in 1984. They'd also become the third team to accomplish the feat in the last four years.

Here's a look at the five 8-over-1 upsets in postseason history:

Nuggets over SuperSonics, 1994

The best-of-five series began in predictable fashion, with the 63-win Sonics of Gary Payton and Shawn Kemp coasting to two home victories over the 42-win Nuggets, a young team led by fourth-year guard Mahmoud Abdul-Rauf, third-year center Dikembe Mutombo and second-year forward LaPhonso Ellis. But Denver rebounded with two home victories and then stunned the favorites in overtime in Seattle, where George Karl's Sonics had lost four times all season. Mutombo blocked eight shots in Game 5 and a record 31 in the series. Sports Illustrated's Chris Ballard reported in this week's magazine that Ellis saw Karl recently and the former Seattle coach told him, "Your greatest moment was the worst moment in my coaching history."

Knicks over Heat, 1999

The third of four consecutive playoff meetings between the bitter rivals brought the drama, if not much offense. The best-of-five series -- which followed a lockout-shortened 50-game season in which Miami (33-17) and New York (27-23) were separated by six games -- wasn't decided until Knicks guard Allan Houston's go-ahead 14-foot leaner bounced in with 0.8 seconds left in Game 5. "Life in basketball has a lot of suffering in it, and we will suffer this one," Heat coach Pat Riley said. New York is the only team on this list to keep advancing after its first-round upset. The Knicks won the East, despite losing Patrick Ewing to an Achilles injury in the conference finals against the Pacers, before falling to the Spurs in the NBA Finals.

Warriors over Mavericks, 2007

Golden State's first playoff appearance in 13 years was a memorable one and particularly satisfying for Don Nelson, who coached Dallas for eight seasons and had an acrimonious relationship with its owner, Mark Cuban. The "We Believe" Warriors (42-40) used hot shooting from Baron Davis and Stephen Jackson to subdue the Mavs, a 67-win team with the league MVP in Dirk Nowitzki, who shot 2-of-13 in a season-ending 111-86 loss in Game 6. "This series I couldn't put my stamp on," Nowitzki said.

Grizzlies over Spurs, 2011

Marc Gasol (left) and Zach Randolph lifted Memphis past San Antonio in 2011. (Joe Murphy/NBAE via Getty Images)

The core of the Memphis team that is giving Oklahoma City fits in this year's first round did the same to San Antonio (61-21) three years ago. The Spurs averaged only 102.8 points per 100 possessions in the six-game series, according to Basketball-Reference, a full nine points below their season average, which was second in the NBA. Playing without an injured Rudy Gay, the Grizzlies (46-36) got enough offense from Zach Randolph, Mike Conley and Marc Gasol to win a series for the first time in their 16-year history.

76ers over Bulls, 2012

Andre Iguodala had a game-high 20 points, including two crucial free throws, in the Sixers' series-clinching win. (Matt Slocum/AP)

After a 50-16 finish in the lockout-shortened season, Chicago's championship hopes were crushed when Derrick Rose sustained a torn left ACL in the fourth quarter of Game 1. Joakim Noah went down during the series, too, leaving the Bulls vulnerable against a Sixers team that defended nearly as well as Chicago did. The winning team failed to reach 80 points in three of the last four games, including the Game 6 clincher, when Philadelphia prevailed 79-78 on Andre Iguodala's go-ahead free throws with 2.2 seconds left. The Sixers (35-31), who advanced for the first time since 2003, went on to lose to the Celtics in seven games in the second round.

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