The Nationals’ didn’t give Yunesky Maya any run support, leading to the team’s seventh loss in as many games started by the Cuban right-hander. (Christian Petersen/Getty Images)

When Yunesky Maya arrived back in the major leagues last weekend, the Washington Nationals hoped his second stint would be different. He had gained comfort in America. He better understood the style of baseball in the majors. He knew what to expect and felt like he belonged.

One week later, the Nationals may have run out of reasons to hope Maya will become the pitcher they expected he would be. Maya’s results, after he lasted 41 / 3 innings and the Arizona Diamondbacks beat the Nationals, 4-0, Friday night, have not changed at all, including the one that matters most. When he pitches, the Nationals lose. Maya has started seven games in the majors. The Nationals haven’t won any of them.

In losing his latest, which snapped a three-game Nationals winning streak, Maya received plenty of help. He left the game with the bases loaded down a run, and watched as Doug Slaten jogged into the game and surrendered a three-run triple. The Nationals’ offense was shut out for the eighth game this season, primarily by right-handed rookie Josh Collmenter, who has a 1.25 ERA and who throws as if he’s about to scratch his back, then decides to hurl a pitch instead.

While Maya was not the only culprit, he again provided little reason to believe he’ll turn into the pitcher the Nationals wanted when they signed him last summer to a four-year, $6 million contract. He lasted less than five innings for the second straight start, allowing six hits and three walks. Like most of his starts, he avoided major trouble and then crumbled in one inning. In seven career starts, he has a 6.43 ERA.

“He’s in these situations a lot,” Manager Jim Riggleman said. “He puts you in that situation where, you’re trying to get him through five. That seems to happen in the middle of the ballgame. You can’t keep getting in these situations. I don’t know what to tell you.”

Still, in five days, the Nationals plan to send Maya to the mound. His next start will come June 8, also the date Tom Gorzelanny, the left-hander Maya replaced in rotation, is set to come off the disabled list. But Riggleman said Gorzelanny will need work before he joins the team on their current road trip and is “a long shot” to join the team.

So Maya will get another chance.

“He finally realized he needs to pitch,” catcher Ivan Rodriguez said, translating answers from Maya as he took questions from reporters. “No throwing the baseball. He needs to locate and throw the baseball where he wants to throw it next time.”

Maya’s only significant blemish in his first four innings Friday came when Chris Young crunched a solo homer to left to lead off the second. The Nationals trailed only 1-0 until the fifth inning. But Maya has yet to start without collapsing in a given inning, and so the fifth carried with it a sense of dread.

Maya, true to form, followed up two scoreless innings by walking Collmenter, the pitcher, on five pitches to start the fifth — “the key at-bat,” Riggleman said. Ryan Roberts followed by lashing a double to left-center on the first pitch he saw. Maya struck out Kelly Johnson on a 67 mph curve, and for a brief moment, it appeared like he might wiggle out of the jam. Then he drilled Justin Upton with the first pitch he threw.

Riggleman emerged from the dugout and, with lefty Stephen Drew walking to the plate, called for Slaten, the left-hander he uses against lefties in mid-inning jams. Slaten has gotten out of few of them. On Wednesday, he entered with the bases loaded and escaped only when Laynce Nix made a breathtaking diving catch.

Slaten threw Drew three consecutive balls, and the crowd, sensing a crucial moment, rose and cheered. Slaten grooved a 90 mph fastball, and Drew treated it like batting practice. He crushed a triple off the center field wall, scoring three runs and putting the Nationals in a 4-0 deficit.

After an excellent 2010, Slaten has allowed 15 of 30 inherited runners to score this season. He has allowed nearly six walks and more than 12 hits per nine innings. He is still searching for the difference between his dominance last year and his struggles this season. “Good question,” Slaten said. “I don’t have an answer for it.”

“I don’t know that he’s really 100 percent right now,” Riggleman said. “The results are so different than what we had seen last year. I check with him all the time. He says, ‘I’m fine, I’m fine.’ I know he’s better than this, you know?”

With Collmenter on the mound, the runs served as overkill. The Nationals offense, after showing signs of surging recently, managed three hits of Collmenter in seven innings. Then again, none of his opponents has solved his funky delivery.

Collmenter winds up, brings the ball behind his left ear and then throws directly over his head, almost across his body. No one in baseball throws quite like him, and the Nationals looked appropriately perplexed. But, they said, Collmenter’s pitches, especially his change-up, mattered more than his delivery.

“I felt 100 percent comfortable, personally,” second baseman Danny Espinosa said. “I saw the ball well. I don’t think anything threw me off. He has a good change-up, but I didn’t feel uncomfortable.”

In their previous five games, the Nationals had seemingly started to fix their offensive woes, scoring 26 runs on 53 innings. In just those five games, they raised their team batting average from .227 to .334. Friday, they reverted.

So, for Friday night, it may not have mattered how Maya pitched. Five days from now, he’ll try again to win for the first time, to see if he can be different from what he’s been so far.

“It worries him a little bit,” Rodriguez said. “He wants to win.”