Tampa Bay’s penalty kill ranked 28th in the NHL during the regular season. (Chris O’Meara/AP)

Now that the Pittsburgh Penguins are in Washington’s rear-view mirror, the Capitals need to focus on their Eastern Conference finals opponent, the Tampa Bay Lightning.

The Lightning has a lot in common with the Penguins‘ two most recent championship teams: star power, the ability to roll four lines and a tremendous presence in net. But there is one thing Tampa Bay is not good at, and that’s killing penalties. Tampa Bay’s penalty kill ranked 27th in the NHL during the regular season (76.1 percent), with Coach Jon Cooper calling it a “sore subject” in February.

Tampa Bay tried to fix its penalty-killing unit. The team acquired center J.T. Miller and defenseman Ryan McDonagh from the New York Rangers at the trade deadline plus gave rookie Anthony Cirelli more ice time, but none of it helped. The Lightning’s efficiency has actually declined to 70 percent since March, and Tampa Bay has allowed eight goals on 31 power plays (74.2 percent kill percentage) in the playoffs.

“We make every power play look like they’re the best power play in the league,” Cooper told Joe Smith of the Tampa Bay Times.

Effective penalty-killing units are able to deny the opposition from carrying the puck into the offensive zone by applying puck pressure and controlling the blue line. And the best penalty killers do this by moving their feet and positioning their body and stick to cut off skating and passing lanes. Unfortunately for Tampa Bay, it has trouble gaining control of the puck right at the start in the faceoff dot.

The team is winning just 43 percent of its shorthanded faceoffs in the regular season and playoffs combined, third worst in the NHL behind the Colorado Avalanche (38 percent) and Calgary Flames (42 percent), a non-playoff team. If Tampa Bay is unable to gain possession it becomes more difficult for it to clear the puck and, perhaps worse, it’s more likely to lead to a quality shot on net. The Lightning allows the fourth-most scoring chances per 60 minutes (62) on the penalty kill in the playoffs. The three teams worse than it — the Anaheim Ducks, New Jersey Devils and Columbus Blue Jackets — were all eliminated in the first round, as was the fifth-worst team, the Toronto Maple Leafs.

An inability to win faceoffs and proclivity to allow prime chances is a double whammy that plays right into the strengths of the Capitals, a team that boasts one of the best power-play units in the NHL. Washington scored on 55 of its 244 opportunities during the regular season (22.5 percent, seventh best in the league) and has converted on 13 of 42 (31 percent) of its postseason opportunities while utilizing its now famous 1-3-1 system, which “creates four triangles to pass around and take one-timer shots” while forcing “the defense to focus on the middle players, causing the penalty kill to shrink.”

The Capitals scored just four times in 15 tries with the man advantage during the second-round series against the Penguins, with superstar Alex Ovechkin taking only one shot attempt from his “office,” near the dot of the left faceoff circle, because of Pittsburgh shadowing Ovechkin, a strategy Tampa Bay used in its first regular season meeting with Washington this season.

As you can see in the image below, Tampa Bay forward Ryan Callahan keeps tabs on Ovechkin during one of Washington’s power plays, with the rest of the Capitals engaging in a four-on-three situation. John Carlson wisely takes a shot from the point, using T.J. Oshie as a screen. Oshie would deflect the puck past Andrei Vasilevskiy, giving Washington its second goal of the first period.

However, Tampa Bay abandoned this approach in the next two regular season games, allowing Ovechkin to generate 10 shot attempts, seven of those scoring chances, over that span. He didn’t score a goal, but the more you allow Ovechkin to try his luck, the more likely he is going to end up lighting the lamp. Still, the Lightning was stingy with shot attempts from that area of the ice during the regular season, creating opportunities for the other members of the Capitals’ top power-play unit — Carlson, Oshie, Nicklas Backstrom and Evgeny Kuznetsov — to get Washington on the board.

And that might be easier than you think. As good as Vasilevskiy has been, stopping pucks on the penalty kill hasn’t been one of his strengths. According to the hockey analytics site Corsica, based on the quality of shots he has faced, the Vezina Trophy finalist should have a penalty-kill save percentage of .888, not his actual save rate of .866, in the regular season and playoffs combined. Plus, he is surprisingly porous on both medium and high-danger chances, resulting in below-average save rates for each.

Why focus on one weakness for the Lightning when everything else about it appears to be championship caliber? Since 2006, only the 2015 Chicago Blackhawks won the Stanley Cup with a penalty kill rate below 80 percent in the playoffs, and theirs was only barely below that mark at 79 percent. If Tampa Bay is to win the second title in franchise history, the penalty kill is going to have to be the best we’ve seen all season.

Read more on the Capitals:

The 13 excruciating playoff losses that had D.C. sports fans starving for one more Capitals win

Capitals’ win puts a dagger in the D.C. sports ‘curse’

Sudden end leaves Penguins in unfamiliar position

Washingtonians go bonkers after Caps’ overtime win

Evgeny Kuznetsov’s winner: Watch it, listen to it, never forget it

That Caps win was Washington’s biggest since …