Andy Najar of D.C. United is given a red card and ejected from the game by referee Jair Marrufo against New York on Saturday night. The teams play again Wednesday. (Patrick McDermott/Getty Images)

The early stages of the MLS playoffs aren’t so much multi-game series as they are 180-minute matches played in two venues several days apart.

D.C. United and the New York Red Bulls are at halftime. The score is tied.

The clubs exchanged own goals and critical saves Saturday at RFK Stadium before settling for a 1-1 draw.

Advantage: Red Bulls.

Ten years ago, after utilizing American-style, three-game playoff formats in the league’s first seven seasons, MLS adopted the international standard for knockout competition: Each side hosts one game, with total goals deciding the winner. The only difference is MLS doesn’t use away goals as the first tiebreaker in case of a two-game deadlock.

If United and New York tie again Wednesday night at Red Bull Arena, a full 30 minutes of overtime would commence. No outcome would necessitate penalty kicks.

Although tying at home in a short series often feels like a loss, United took comfort in its performance Saturday.

“We played well enough to win but we didn’t,” said midfielder Chris Pontius, whose club is riding an eight-game unbeaten streak. “So it’s a 90-minute game now and it would be even sweeter to take it from them up there.”

As the higher seed in the Eastern Conference semifinals, No. 2 United earned the right to host the third-seeded Red Bulls in the decisive second leg in Washington. But Red Bull Arena was unavailable over the weekend because of Hurricane Sandy’s impact. Thanks to United’s goodwill, the league was able to swap home dates.

As part of the agreement, MLS and the Red Bulls agreed to provide free tickets to 500 United supporters. United is paying for at least nine buses.

Commissioner Don Garber gave assurances Saturday that the Harrison, N.J., facility would be up and running in time. The weather promises unpleasant playing and viewing conditions; early forecasts call for a game-time temperature of 41 with rain and wind.

In preparing for the second leg, United Coach Ben Olsen’s first task is selecting a replacement for Andy Najar at right back. Najar was ejected in the second half Saturday after consecutive yellow cards, the second for whipping the ball at referee Jair Marrufo.

Veteran Robbie Russell is the most logical choice.

“We’ll adjust. That is what we’ve been doing all year,” Olsen said about a squad that lost starters Daniel Woolard (concussion) and Dwayne De Rosario (sprained knee) for long stretches late in the regular season.

Russell, 33, began the season as the first-choice right back but missed two months with a foot injury. Second-year player Chris Korb stepped in, but when Woolard went down, Korb moved to the left and Najar, a wing throughout his three-year career, dropped from midfield. Despite novice defensive skills, he offered clever footwork and speed to augment the attack.

Since returning in mid-September, Russell has made three appearances totaling 12 minutes.

Olsen was pleased with his team’s rhythm and movement, but as the case has been since De Rosario departed in early September, United lacked a killer instinct around the penalty area. The club has scored multiple goals in just one of the past seven matches.

United has been playing with one striker, Lionard Pajoy, who has contributed in blue-collar ways but continues to labor with scoring opportunities. Olsen has stuck with Pajoy over Maicon Santos and Hamdi Salihi.

“His work rate is unbelievable and it gives us a dimension that is necessary for this group,” Olsen said of Pajoy. “Yeah, we would like more quality in the finishing. So would he. If he doesn’t score, he is still giving you so much in holding the ball up, doing a lot of the dirty work that a lot of people can’t appreciate.”

As for the task ahead, United doesn’t seem the slightest bit unnerved about having to win the series on the road.

“I’m sure New York feels pretty good about going home,” United President Kevin Payne said, “but we feel good about how we played and how we match up with this team.”