Rockies outfielders Carlos Gonzalez, below, and Dexter Fowler collide at the wall after giving chase to Ryan Zimmerman’s drive in the sixth inning Wednesday. Zimmerman ended up with a double. (Doug Pensinger/Getty Images)

Ten weeks into this Washington Nationals season of disappointment and injury, a starter plucked the day before from the minor leagues stood on the mound here at Coors Field on Wednesday night and provided life. These Nationals have been worn by the weight of high expectations and injuries that have disabled their star hitter and two-fifths of their starting rotation. Yet right-handed starter Ross Ohlendorf, pitching in a major league game for the first time in 10 months, delivered one of the most uplifting performances of this season.

Ohlendorf, perhaps the seventh starter in the organization’s hierarchy, tossed six valiant innings and conceded only one run to a high-scoring Colorado Rockies team in a hitter-friendly ball park in a 5-1 win. Powered by Ian Desmond, a struggling offense provided five runs, eight hits and a season-high eight walks, enough to boost Ohlendorf and the Nationals back to .500 and six games behind the first-place Atlanta Braves, who were swept by the Padres after a 5-3 loss.

“I was excited to be here,” Ohlendorf said. “I’ve been feeling really good all season. It’s the best I’ve felt in a long time. I was really happy we were able to get a win. A fun game for me.”

Ohlendorf’s performance was enough to convince Manager Davey Johnson that the right-hander should stay with the Nationals longer than a day and serve as insurance for Stephen Strasburg.

“An outstanding effort and I’m looking forward to seeing more of him,” Johnson said.

The Post Sports Live crew discusses the possibilites of why Bryce Harper had a brace on his knee after seeing Dr. James Andrews on Monday. (Post Sports Live)

In a season with more questions than encouraging developments, the 30-year-old Ohlendorf, just 4-5 with a 4.27 ERA at Syracuse, gave the Nationals a needed lift. With Ross Detwiler and Strasburg soon to come off the disabled list, the Nationals still needed a starter.

Ohlendorf would have started Saturday if rain hadn’t postponed two games last week and changed the schedule. Ohlendorf, a Princeton graduate and only the second Nationals player to hail from the Ivy League, would have to wait. He last pitched for Syracuse six days earlier. He flew in from upstate New York on Tuesday night.

The Nationals signed Ohlendorf this winter for moments like this. Last year, no Nationals starters suffered no significant injuries and they used eight starters all season. As of Wednesday, Detwiler and Strasburg have both been out of action since late May and Ohlendorf represented their eighth starter of the season.

Ohlendorf, with his fourth major league organization, has the stuff to strike out batters, [he boasted an 8.4 strikeout rate at Syracuse], but has been prone to command issues, issuing 30 walks in 71 2 / 3 innings. But over his past three starts for Syracuse, Ohlendorf punched up a 1.56 ERA with 27 strikeouts over 17 1 / 3 innings. This was the Ohlendorf on display Wednesday.

“I know he was hungry to get back to the big leagues,” Desmond said. “That’s the outing we’ve been needing all year long.”

Ohlendorf’s windup, reminiscent of the sport’s older pitching motions, is a confluence of moving parts. He stands with his back foot near the third base side of the rubber, rocks on his left foot and swings both arms back behind his body. The windup delivery was new this season, an old suggestion from a Pirates coach when he played for Pittsburgh.

“It helps me, gives me rhythm and it helps me stay loose and the ball has been coming out well pitching that way,” he said.

The uncommon delivery, coupled with his location and change of speeds, fooled hitters for most of six innings. Ohlendorf lived on the outer edges of the strike zone. When he ventured into the heart of the plate, he miraculously escaped unscathed. The movement on his fastball kept batters from making solid contact.

“Sometimes it’ll cut a little bit and the ball sinks late so that’s good,” catcher Jhonatan Solano said. “Sometimes he doesn’t throw it on purpose. We took advantage.”

Ohlendorf tossed only 89 pitches, pairing 92 to 93 mph fastballs with a biting slider. He allowed only two hits, the final one coming in his last and only challenging inning. Rockies slugger Carlos Gonzalez tripled with two outs to plate a run and trim the deficit to 4-1. Up next stepped another slugger, Troy Tulowitzki. He smashed to two balls — a slider and then a change-up — deep, but foul, into the stands. Ohlendorf then fired a 93 mph fastball down the middle and Tulowitzki hit it hard to center but into the glove of Denard Span

The Nationals manufactured enough offense to support Ohlendorf. They worked left-handed starter Jorge De La Rosa enough to chase him after 5 1 / 3 innings and 96 pitches. Desmond gave Ohlendorf a 1-0 lead in the fourth with an RBI single, which extended his hitting streak to a career-high 14 games.

The Nationals then delivered a crucial inning of breathing room in the sixth. With Jeff Kobernus on first after a one-out walk, Ryan Zimmerman lifted a ball to the wall in deep left-center that fell in as Dexter Fowler and Gonzalez collided.

Desmond delivered a two-out, two-run single against reliever Adam Ottavino to push the lead to 4-0. Adam LaRoche was intentionally walked and a wild pitch moved Zimmerman and LaRoche into scoring position. Desmond then lined a 90 mph fastball in center field, capping a three RBI night.

The Nationals’ have struggled offensively for various reasons, but not because of Desmond. He is hitting .358 (19 for 53) during his hitting streak. He hasn’t made an error in 45 games, the longest active streak among shortstops in the majors. After defensive miscues to start the season, Desmond hasn’t made one since committing his seventh on April 21.

After Rafael Soriano tossed a scoreless ninth inning, the Nationals high-fived each other on the field and retreated happily to the clubhouse. But none was more important to this heartening moment than the pitcher flown in from Syracuse the day before.

“I was really excited about this start,” Ohlendorf said. “I’m glad it went well.”