They do know this: They'd rather be 4-0 against the team that traditionally dominates them in the postseason, rather than 0-4.
Crosby had a goal and two assists to give the Penguins captain his fourth 100-point season in five seasons -- he missed only when he sat out two months of 2007-08 with a high ankle sprain -- but Pittsburgh still lost its fourth in a row to Washington.
Ovechkin had four goals in 18 games before scoring on a power play early in the third, then added an empty-net goal with a second remaining. Nicklas Backstrom set up both during a three-assist game, giving him 67 assists.
"I've had lots of chances to score goals, and finally it did go in," said Ovechkin, who had one goal in seven games. "The last 10 minutes, I just felt unbelievable."
The Capitals hope Ovechkin feels that way for about two weeks should the longtime rivals meet up again.
Pittsburgh played without star forward Evgeni Malkin, who missed his eighth game in his last 10 -- this time with an undisclosed illness that caused him to leave the ice a few minutes into the pregame warmup. He missed five games with a bruised right foot before scoring during a 4-3 overtime victory over Atlanta on Saturday.
The Capitals had little to play for except any possible momentum that sweeping the Stanley Cup champions might generate, yet won their second in as many nights and fourth in a row. Washington already is assured of being the top seed in the Eastern Conference playoffs.
"We haven't had much to play for, but we talked about rolling into the playoffs on a high and we didn't do that last year and it cost us the first two games against [the Rangers in the first round] and made it a seven-game series," Matt Bradley said. "The longer series take a toll on you."
So has Pittsburgh, which beat Washington in a memorable seven games last spring -- the Penguins' seventh playoff series win in eight attempts against Washington.
"It's nice to not give them too much confidence in beating us, but the playoffs are a whole new game and they're a dangerous team," Bradley said. "It doesn't mean anything when it comes to the playoffs, and everybody knows they're a playoff team."
The Penguins lost their fifth in eight games and slipped into fourth place in the conference, two points behind Atlantic Division leader New Jersey and one behind Northeast Division champion Buffalo. The Devils beat Atlanta 3-0 and the Sabres defeated the Rangers 5-2.
Pittsburgh is winless in 10 games this season against the Capitals and Devils, dropping all six to division rival New Jersey.
"I think that's huge," defenseman Tyler Sloan said of the Capitals' sweep. "The playoffs are the start of a whole new season. But it feels good for us. ... I think last year's playoff experience we gained is invaluable."
Penguins forward Jordan Staal felt it was important to win and not go winless against two teams Pittsburgh might see again.
"Yeah, it's disappointing, but you've got to move forward," Staal said. "Hopefully, we'll see these guys again."
Penguins coach Dan Bylsma pulled goalie Marc-Andre Fleury after Tomas Fleischmann made it 3-1 only 21 seconds after Crosby scored on a power play to get Pittsburgh within a goal. As Penguins forward
Maxime Talbot drove Alexander Semin into the boards, the puck came loose, Fleischmann grabbed it and beat Fleury with a wrist shot at 6:42 of the second.
An angry Fleury broke his stick against a wall as he walked down a tunnel leading to the dressing room.
"We kept having to restart and try to get back to our game, and that was tough," Bylsma said.
Penguins defenseman Jordan Leopold scored twice around Bradley's 10th goal for Washington, giving him three goals in two games after he didn't score in his first eight games with Pittsburgh.
Ovechkin restored Washington's two-goal lead four seconds after Bill Guerin drew Pittsburgh's only penalty, a high-sticking call at 2:33 of the third.
Earlier, Semin scored his 39th goal, and Mike Knuble's fourth goal in as many games against Pittsburgh this season -- on a seemingly harmless wrist shot from the right circle -- made it 2-0 with 42 seconds gone in the second.
Semyon Varlamov made 26 saves in his first regular-season start against the Penguins.
Capitals D Mike Green rested for a second successive night. He leads all NHL defensemen with 74 points. ... Washington ended 24-10-7 on the road. ... Washington has won seven of eight from Pittsburgh the past two seasons. ... Washington went 6-0-1 against Pittsburgh during the 1984-85 season.