WASHINGTON—There was something that seemed unfair, almost poignant, about the way Game 1 of this first-round playoff series turned against the Rangers on Thursday night.

With the game tied midway through the second period, the Washington Capitals handed the Rangers a gift: a two-man power play 56 seconds long. Yet despite controlling the puck in Washington's zone for most of that time, despite two point-blank shots on goaltender Braden Holtby during the two-man advantage and a third as it was ending, the Rangers didn't score.

The Capitals' Alex Ovechkin scored on a power play Thursday. Reuters

Later in the period, the Capitals did, twice with ease in a 46-second span to win, 3-1, and give life to a question that has hounded the Rangers for years: Why is their power play so lousy?

"Inconsistency," said defenseman Michael Del Zotto, who plays the point on one of the team's power-play units. "We have the talent here. We feel confident in our group. But the last couple of years, it's been inconsistent."

Truth be told, Del Zotto was kind to use that word to describe the Rangers' power play. They went 0-for-4 on Thursday, and though their failure to score cost them the chance to steal a postseason victory on their opponent's home ice, it was pretty much standard operating procedure for them.

They had the 23rd-best power play in the NHL this season—the sixth consecutive year they ranked no better than 13th. Four times over that span, the Rangers have had one of the eight worst success rates in the league. The last time the Rangers had a top-10 power play was 2006-07, when they scored on 18.5% of their man-advantage situations to rank eighth. Unfortunately for them, just three players from that team are still on the roster, and one of them is goaltender Henrik Lundqvist.

The other two, forward Ryan Callahan and defenseman Dan Girardi, are mainstays on the Rangers' current unit. Callahan led the Rangers last season with 13 power-play goals, and Girardi is generally smart and steady—essential qualities for a player manning one of the two point positions.

But since that '06-07 season, when they had Jaromir Jagr and Brendan Shanahan, the Rangers have lacked players with either a fearsome shot or the exceptional creativity necessary to generate scoring opportunities: the individual skills that often make a power play effective.

Consider the Capitals' first goal Thursday (which came on the power play). At first, it would seem an unlucky matter of circumstance for the Rangers: Washington defenseman Mike Green blasted a slap shot wide of the net, but the puck caromed off the boards to Alex Ovechkin, who lifted it over Lundqvist. Bad break, right? Not totally.

Because Green has such a hard, heavy slap shot and can score from great distances with it, all four Rangers on the ice shifted in his direction when he released the puck, leaving Ovechkin—the league leader in goals this season with 32—open at the side of the net. No member of the Rangers' power-play units commands the sort of attention as Green or Ovechkin, and the Rangers suffer for it.

"That's why they have a successful power play," Callahan said. "They've got a lot of threats. They've got a lot of guys who can pound the puck, and it's tough to defend."

The Rangers have experimented with varying formations and tactics this season trying to find a power-play formula that works. The latest iteration has Rick Nash—their most gifted offensive player—stationed in the high slot "to occupy some people there, create more open ice for other guys," Del Zotto said. "We have to keep it simple."

In hockey lingo, "keep it simple" means "put as many guys as you can in front of the net to block the goalie's vision and shoot from everywhere." That has pretty much been the Rangers' approach for six years now. They are still waiting to reap the benefits.


Game 2 (WSH 1-0)

Sat. 12:30 p.m., NBC

Write to Mike Sielski at mike.sielski@wsj.com