Both teams were last in action on Tuesday. Boston extended its perfect run following the NHL's holiday break (4-0-0) and returned to the top of the overall league standings with a 4-1 win at Columbus, while a 4-3 home setback against Washington ended Pittsburgh's 5-0-1 streak.
Bruins forward James van Riemsdyk used a three-point effort at Columbus to emerge as the latest star during Boston's recent surge. The victory was more evidence that the break came at a great time, with the Bruins moving past a season-long losing streak before Christmas (0-2-2).
"We were playing a little bit uneven going into (the break)," van Riemsdyk said. "We really took advantage of that as far as hitting the reset and kind of getting back to the things that made us successful."
van Riemsdyk, who was scratched for Boston's 5-3 win at Detroit on Sunday, made an immediate impact with new linemates Trent Frederic and Danton Heinen against the Blue Jackets. The trio scored Boston's last three goals.
"Really pleased. They played a big, heavy game," Bruins coach Jim Montgomery said. "I thought the third goal (by Heinen) that extended the lead was huge for us."
Lineup decisions will become even harder with rookie forward Matt Poitras due back in Boston after his IIHF World Junior Championship stint with Canada ended on Tuesday in the quarterfinals.
Forward Georgii Merkulov played in three games since being recalled from AHL affiliate Providence.
"(Poitras) won't be an option for (Thursday), and then we'll start discussing integration back into the lineup," Montgomery said.
Defenseman Mason Lohrei, who was hit in the mouth with a puck and required stitches on Tuesday, should be available against Pittsburgh.
Pittsburgh spotted Washington a 4-0 lead in Tuesday's first period, but a three-goal comeback fell just short against a team that it was tied with in the Metropolitan Division entering the game.
"I didn't think (goalie Tristan Jarry) had his best, but I didn't think the team had its best either early in the game," Penguins coach Mike Sullivan said. "I loved our compete level and climbing back in the game. We certainly made it a game, but we can't spot a team those types of goals early on."
Sidney Crosby, who passed Joe Thornton as the 12th-leading point scorer in NHL history with 1,540, was one of three Penguins to post a goal and an assist.
Despite the loss, the Penguins are within three points of rival Philadelphia, which holds the No. 1 wild-card spot in the Eastern Conference, although four other teams also are within three points.
The Penguins' recent win streak included a pair of two-goal victories following a 7-0 shutout of the New York Islanders.
Jarry and Alex Nedeljkovic, who entered in relief against Washington, had a .910 save percentage during the Penguins' 7-3-3 December.
The Penguins' penalty kill has been especially strong lately. Washington scored only the second power-play goal allowed by Pittsburgh over its last seven games after giving up five in a three-game span.
"Some guys might be playing with different guys," said Penguins forward Noel Acciari, who played with the Bruins for four seasons from 2016-19. "But all in all, we're just kind of all on the same page, knowing each other's jobs."
Tuesday marked the return of Penguins forward Bryan Rust, who had been out with an upper-body injury since Dec. 6.
Pittsburgh defenseman John Ludvig (upper body) was placed on injured reserve on Wednesday, with Ryan Shea recalled from Wilkes-Barre/Scranton.