Matt Kemp’s walk-off single lifts Dodgers in 10th inning

The Dodgers pitcher who held the Houston Astros scoreless for six innings was playing for double-A Chattanooga little more than a week ago.

The Dodgers shortstop who started a double play in his debut for the team was a major league nobody, at least according to most rankings of baseball prospects.

And so what has seemed like a lost season in L.A. continues to generate a few unexpected finds.

Making only his second major league start, Nathan Eovaldi limited his hometown Astros to two hits through six innings Friday night at Dodger Stadium and shortstop Justin Sellers played flawless defense in his first game of the season not wearing a hat with a funky “A” design.

Matt Kemp made them both winners with a bloop single down the right-field line with none out in the 10th inning that drove in Casey Blake from second base and gave the Dodgers a 1-0 victory, snapping their four-game losing streak.

Blake had led off the inning with a double down the right-field line. The Astros, who had triggered an audible groan from the crowd an inning earlier when they escaped a no-out, bases-loaded jam, intentionally walked Andre Ethier to bring up Kemp.

The cleanup hitter delivered against reliever David Carpenter.

It was a thrilling conclusion to a day in which the Dodgers signed first-round draft pick Chris Reed and one of their top scouting executives rejected criticism that the organization’s minor league system was depleted.

Logan White, the Dodgers’ assistant general manager for scouting, pointed to Eovaldi, who sparkled for the second time in seven days, and closer Javy Guerra, who pitched a perfect ninth inning Friday, as under-the-radar prospects who have produced at the major league level.

“Javy Guerra is ranked nowhere by anybody,” White said. “People tend to forget about these guys because they’re not sexy, they’ve been around a little while.”

More help could be on the way. White touted pitcher Allen Webster, infielder Scott Van Slyke and catcher Griff Erickson as minor leaguers to watch.

“We’ve got a lot of guys down there who are really good,” said Eovaldi, who has held opposing hitters to a .162 average with 10 strikeouts in 11 innings.

Sellers wasn’t even considered the best shortstop on his minor league team for most of the season. That honor went to Dee Gordon, whose second stint with the Dodgers was put on hold Friday when he was placed on the disabled list because of a bruised right shoulder.

Gordon’s injury opened a spot for Sellers, who was promoted from triple-A Albuquerque. That provided the Southern California native a chance to step on the same field where he had watched Mike Piazza and Eric Karros play growing up.

“It’s amazing, man,” said Sellers, 25, who was hitting .304 for the Isotopes. “I couldn’t really sleep the past couple of nights.”

Eovaldi might have been forgiven had he been jittery against the Astros, whom he grew up rooting for.

“It was real cool to face them,” said Eovaldi, who escaped a bases-loaded, one-out jam in the fourth.

“I’ve always watched the Astros.”

ben.bolch@latimes.com