Salt Lake's Joao Plata, left, loses a header to United forward Lionard Pajoy. Pajoy scored the winning goal in the 60th minute. (John McDonnell/THE WASHINGTON POST)

On an artistic scale, D.C. United’s 1-0 victory over Real Salt Lake on Saturday did not rate very high. There were a few stretches of grace, an opportunistic goal and a sound defensive performance. For the most part, though, this was one of those blue-collar efforts that carried United into the MLS playoffs last season.

United welcomed Lionard Pajoy’s header off a rebound in the 60th minute, then clamped down during an anxious finish to extend its home unbeaten streak against league opponents to 19. Real (1-1-0) is winless in nine all-time appearances in Washington.

Neither team manufactured many quality chances in front of 17,072 at RFK Stadium, but United (1-1-0) was tighter in the back and exposed goalkeeper Bill Hamid to just a couple threats.

“The back four was very connected,” Coach Ben Olsen said. “We weren’t connected and we didn’t look out for each other in Houston” last weekend, a 2-0 defeat in which United conceded several opportunities.

With Dwayne De Rosario serving the last of his two-game suspension, United’s attack was out of sorts at the start but improved as the match unfolded.

The breakthrough came when John Thorrington gathered a Real clearance and chipped a shot from distance toward the upper left corner. Nick Rimando made a breathtaking save, but the unmarked Pajoy, who had been kept onside by Sebastian Velasquez, headed in the rebound.

“It’s one of those plays where, as a forward, you are always aware of what might come out of it,” Pajoy said through an interpreter. “I was able to make it happen. Those are the situations you want to take advantage of.”

Pajoy is a puzzling and sometimes infuriating player to watch. He misses scoring opportunities regularly but does the dirty work that Olsen asks of him — pressuring defenders, holding the ball, getting back on defense. And at times, he registers a pivotal goal.

“Everyone on this team likes playing with him,” midfielder-forward Chris Pontius said. “Everyone tends to say, ‘Aw, he’s not the greatest finisher.’ But the work he puts in off the ball is phenomenal for us, and that is what we need from a forward.”

To the chagrin of many United supporters, Olsen has stuck with Pajoy since acquiring him from Philadelphia last summer.

“He scored a goal tonight, the one that won the game, so you’re not going to get any knocks on Pajoy right now from me,” Olsen said.

Pajoy exited in the 83rd minute, allowing MLS veteran Carlos Ruiz to make his United debut. Ruiz could have closed out the game in stoppage time but failed to finish Kyle Porter’s cross.

“You see us at times be a pretty good team — the way we move the ball, the way we get our outside backs involved,” Olsen said. “If you see no light, it’s trouble. But for large stretches of that game, I liked the way we went about it.”

Afterward, the most concern centered on Thorrington, an oft-injured midfielder acquired in the winter. He hurt his left knee in the 74th minute and left the game. He will have an MRI exam Monday.

“It’s heartbreaking for me. I was enjoying myself out there,” he said, declining to speculate on the severity.

Said Olsen: “We don’t think it’s anything season-ending, but there is probably something in there, maybe an MCL.”

Another postgame talking point was a 63rd-minute incident in which Real’s Abdoulie Mansally headbutted Perry Kitchen in the chest. He received a yellow card.

“There was some contact. It was a heated situation,” Kitchen said. “At least it wasn’t my face.”

De Rosario was suspended for two matches for headbutting Philadelphia’s Danny Cruz on the nose in the preseason finale.

“I’m not sure why [Mansally] was still in the game,” Olsen said, suggesting the incident warranted a red card.

The highlight of the first half was what occurred before the game: a choreographed display of colors by the supporters’ groups filling much of the east end that recreated the District of Columbia flag.

The first serious threat came in the 32nd minute when Pontius surged between two defenders and ripped a 12-yarder toward the near side. Rimando was positioned well and slapped it aside.

The second half was much like the first — fleeting possession and tedium amid a restless audience — until Pajoy’s goal.

Hamid’s first serious test didn’t come until the 73rd minute, a manageable one-timer by Khari Stephenson.

Real ramped up the pressure, but United held firm.

“The last 20 minutes were pretty tough,” center back Dejan Jakovic said, “but we managed to get the three points.”