GAME: Atlanta Thrashers (41-32-7) at Washington Capitals (27-41-12).
TIME: Monday, 7 p.m. EDT.
A span of 24 hours will decide whether the Atlanta Thrashers advance to the postseason for the first time or start thinking about next year.
Atlanta looks to move within one point of eighth-seeded Tampa Bay when it faces the Washington Capitals at Verizon Center.
The Thrashers are 7-0-2 with one tie in the series since a 5-0 loss on Dec. 16, 2003.
Atlanta, which has won four straight and is 5-0-1 in its last six games, has 89 points and one game left after this one - a matchup Tuesday at Florida, whom it has beaten five of the last six meetings.
The Lightning conclude their regular season Tuesday when they host the Capitals, while seventh-seeded Montreal, just four points ahead of Atlanta, will take on New Jersey at home.
It Tampa Bay or Montreal loses in regulation Tuesday and the Thrashers win out, Atlanta will earn a playoff spot.
"I really want to make the playoffs," defenseman Andy Sutton said after the Thrashers' 4-3 win over Boston on Saturday. "This is my eighth year as a pro, and I've yet to play in a playoff game. That eats at me a lot."
Sutton scored twice and added an assist against the Bruins, and both Scott Mellanby and Jim Slater each had a goal and an assist for a Thrashers team that trailed 3-2 entering the third.
"In the last 30 games or so, I've been trying to get up into the play and help the offense as much as I can," said Sutton, who has eight goals and a career-high 25 points this season. "I want to be a second-wave threat."
Goaltender Mike Dunham won his fourth consecutive start in place of the injured Kari Lehtonen, finishing with 23 saves.
Thrashers leading scorer Ilya Kovalchuk needs two points in the final two games to become the franchise's first player to reach 100 points in a season, while Marc Savard needs three.
Washington went 2-2-0 on a four-game road trip which concluded with a 2-1 shootout win over the Panthers on Saturday.
Matt Pettinger scored the game-winner in the fourth round of the shootout and Brent Johnson made 47 saves in regulation for the Capitals, who had 53 shots on goal.
Washington had lost its last eight meetings with Florida.
"I pretty much knew I needed to do something different," said Pettinger, who was stopped on a penalty shot in the first. "The five hole opened up and I put it there."
Rookie Alexander Ovechkin scored his team-leading 51st goal midway through the second.
Ovechkin, who became the second player in NHL history to garner 50 goals and 100 points in his first season when he scored against the Thrashers in a 5-3 loss Thursday, has four goals and eight assists in seven games versus Atlanta.
STANDINGS: Thrashers - 89 points, 3rd place, 23 PB, Southeast Division. Capitals - 66 points, 5th place, 46 PB, Southeast Division.
TEAM LEADERS: Thrashers - Kovalchuk, 52 goals and 98 points; Savard, 69 assists; Sutton, 140 PIM. Capitals - Ovechkin, 51 goals, 52 assists and 103 points; Chris Clark, 110 PIM.
SPECIAL TEAMS: Thrashers - Power play: 19.4 percent (100 for 515), 5th in NHL. Penalty killing: 79.2 percent (381 for 481), 25th. Capitals - Power play: 14.6 percent (70 for 480), 27th. Penalty killing: 78.5 percent (419 for 534), 30th.
GOALTENDERS: Thrashers - Dunham (8-4-2, 1 SO, 2.52 GAA); Lehtonen (20-15-0, 2, 2.94). Capitals - Olaf Kolzig (19-28-11, 3.52); Johnson (8-12-1, 1, 3.55).
SEASON SERIES: Thrashers, 5-0-2.
LAST MEETING: April 13; Thrashers, 5-3. At Atlanta, Marian Hossa had two goals and two assists in the Thrashers' third straight win. Ovechkin scored his 50th goal of the season for the Capitals.
ROAD/HOME RECORDS: Thrashers - 17-19-3 on the road; Capitals - 15-18-7 at home.