Patrick Mullins scored eight goals in 14 regular season appearances for United last season. (Jonathan Newton / The Washington Post)

D.C. United is without a victory, without a goal and, for the near future, without Patrick Mullins.

The first-choice striker has been sidelined since straining his left hamstring in the first half against the Columbus Crew on March 18 and probably won’t return for three or four weeks, Coach Ben Olsen said Friday. He would miss four or five MLS matches, starting with Saturday’s meeting against the Philadelphia Union at RFK Stadium.

Olsen listed three possible replacements: Jose Guillermo Ortiz, Sebastian Le Toux and Lamar Neagle.

Ortiz filled the void in the Columbus match but, because of Costa Rican national team duty and two World Cup qualifiers, he trained with United only twice in the past two weeks. (United did not have a game last weekend.) Le Toux made his season debut against the Crew and Neagle, last year’s top scorer, has entered in the second half of all three matches.

Mullins said this is the first time in his life he’ll miss extended time with an injury.

“This isn’t a time when I wanted to miss out on things,” he said. “It’s an important time for our team and I wanted to help right the start we’ve had. That course has shifted, but it’s a long season and I’ll have a role to play.”

His injury came 28 minutes into his first work of the season with playmaker Luciano Acosta, who had missed the first two matches with an ankle injury. Late last year, after United acquired Mullins from New York City FC, the Mullins-Acosta combination triggered a scoring surge and raised hopes ahead of a full season together.

“You’re never going to have your top group all the time and you’ve got to make it work,” Olsen said. “We have the depth to win games in this league, but everyone has to be at a certain standard on the day. If we can do that, we’ll be okay.”

United is averaging 11 shots and four shots on target — respectable numbers — but remains the only team in the 22-strong league without a goal.

In the opener, Marcelo Sarvas failed to convert a penalty kick and Kansas City players cleared two shots off the goal line. In the next match, United had a goal disallowed, then collapsed defensively in falling behind 4-0 to New York City FC before futilely generating a few quality opportunities. Most recently, Acosta’s return led to better rhythm but still no goals, thanks in part to Columbus goalkeeper Zack Steffen’s exceptional work.

“If you actually look at the performances, they are creating chances,” Philadelphia Coach Jim Curtin said. “They’re dangerous. They have a lot of dynamic attackers. It is dangerous when you see they haven’t scored a goal because you do know they have that potent ability to break out.”

Despite the absence of goals, Olsen suggested he plans to stick with most, if not all, of the other starters, including the central pair of Acosta and rookie Ian Harkes. Lloyd Sam and Patrick Nyarko are the incumbent wings.

“All the data shows that we are putting together enough stuff in the final third and putting together high-percentage chances,” Olsen said. “Eventually, they start to go in.”

Olsen cited last year’s slow start (three goals in five matches) before breaking out with seven goals in the next two home matches. United also ended a midseason rut (seven goals in 10 games) by acquiring Mullins and Sam and watching Acosta hit his stride. Mullins finished second on the team in scoring with eight goals, despite just 14 appearances.

“A little extra effort in the box, an extra player in the box, a little better with our crosses — all of that stuff has to get better,” Olsen said. “It will.”

Defensively, Taylor Kemp and Nick DeLeon seem safe on the corners and captain Steve Birnbaum will anchor the middle. Sean Franklin, a former right back who beat out longtime starter Bobby Boswell for a starting job, has partnered with Birnbaum in all three games.

Marcelo Sarvas remains the defensive midfielder; his backup, Rob Vincent, is recovering from knee surgery, performed last week. He’ll return in about a month.

“Take out the New York City game, we’ve been okay,” Olsen said. “But okay doesn’t really cut it. You’ve got to be good on both sides to get wins.”

United notes: Defender Maxim Tissot and midfielder-defender Chris Durkin are with the second-division Richmond Kickers for a USL visit Saturday to defending champion New York Red Bulls II. Forward Alhaji Kamara was held back because of a minor calf injury. … Philadelphia’s career scoring leader against United is United’s Le Toux, who posted seven goals and four assists in 13 meetings across two stints with the Union. … Midfielder Alejandro Bedoya has rejoined the Union after making substitution appearances in the U.S. national team’s World Cup qualifiers against Honduras and Panama.

Referee: Ricardo Salazar.

Weather: 54 degrees, mostly clear, 11-mph wind.


D.C. United vs. Philadelphia Union

Where: RFK Stadium.

When: Saturday, 7 p.m.

TV: NewsChannel 8.

Records: United 0-2-1, 1 point; Union 0-1-2, 2 points.

D.C. probable starters: GK Bill Hamid; Ds Nick DeLeon, Sean Franklin, Steve Birnbaum, Taylor Kemp; MFs Lloyd Sam, Marcelo Sarvas, Ian Harkes, Luciano Acosta, Patrick Nyarko; F Jose Guillermo Ortiz.

Philadelphia probable starters: GK Andre Blake; Ds Keegan Rosenberry, Oguchi Onyewu, Richie Marquez, Fabinho; MFs Fabian Herbers, Haris Medunjanin, Derrick Jones, Alejandro Bedoya, Chris Pontius; F C.J. Sapong.