Roloson made 23 saves for his second shutout in eight days against Washington and the Tampa Bay Lightning beat the Caps 3-0 at the St. Pete Times Forum to grab sole possession of first place in the Southeast Division.
"Do I need to talk? I can just smile," Tampa Bay coach Guy Boucher said. "You know what? He makes so many saves look easy and they're not."
Roloson, acquired in a New Year's Day trade with the New York Islanders, beat the Caps 1-0 in overtime at the Verizon Center on Jan. 4 in his Lightning debut. His new club now has 57 points, two more than the Capitals.
"The result is the same, but at the same time you've got to give my teammates a lot of credit," Roloson said. "Our defensive corps to our forwards, they played unreal tonight."
Dominic Moore, Sean Bergenheim and Simon Gagne scored for the Lightning, who have won seven of 10 to move ahead of Washington. Tampa Bay has missed the playoffs each of the past three seasons, while the Capitals are the three-time defending division champs.
Washington goalie Semyon Varlamov faced 38 shots. He had allowed six goals in his previous five games (4-0-1).
The Capitals are 6-1-3 in their past 10 games.
"It's tough when you've got a team that's used to scoring," Washington coach Bruce Boudreau said. "There's a lot of things not going right for them and they're pressing really hard. But it's not for a lack of want and will."
Moore put the Lightning up 1-0 with an in-close goal 3:58 into the game. Bergenheim made it 2-0 from the low slot with 3:56 left in the first. Roloson earned an assist on the play.
The Lightning went ahead 3-0 when Gagne stopped a personal 11-game goal drought during a 2-on-0 break at 18:18 of the second, racing in and zipping a quick wrister past Varlamov.
"When they scored that first one, we knew we were in for a tough night," Boudreau said.
Tampa Bay defenseman Mattias Ohlund was penalized for cross-checking Washington star Alex Ovechkin with 7:08 to go in the first period. Ovechkin ended the Capitals' second and final power-play of the game after 22 seconds when he received a slashing penalty.
Ovechkin has only two power-play goals this season. Washington has converted three of its last 36 man-advantage opportunities.
Washington has been outscored 39-27 in the first period this season and is 12-12-3 when the opponent scores first. The Capitals fell behind 3-0 before losing 4-3 in overtime against Florida on Tuesday night.
"You can't always expect to come back in games," Capitals defenseman Scott Hannan said. "I think we just weren't ready at the start and it cost us two games."
Tampa Bay All-Star Steven Stamkos didn't have a point, and has one assist over the last six games. He has yet to score a goal in 2011 -- but it hasn't mattered.
"We're going to stay humble," Bergenheim said. "This was a great win, but we've got another game on Friday (against New Jersey), and by then we'll definitely forgot about this."
Material from wire services and team media was used in this report.