OAKLAND -- In the many glowing scouting reports the A’s had received on Shea Langeliers, speed on the basepaths was absent from the large list of impressive qualities he brings to the table. On Sunday, however, the rookie showed he’s also got a decent run tool in his bag.

Langeliers pounced on a first-pitch hanging slider from Matthew Festa with one out in the eighth inning and missed out on a home run by just a few feet, crushing it off the Coliseum’s out-of-town scoreboard in left field. Once Langeliers saw the ball bounce away from Jesse Winker, he turned on the burners and wound up with an RBI triple, completing the trip from home plate to third base in 12.30 seconds.

The triple provided an insurance run in what ended as a 5-3 victory for the A’s, who played spoiler to the playoff-contending Mariners over the weekend by taking two of three from their American League rivals. Beyond being the first triple of Langeliers’ career, it was also downright historic. The triple was Oakland’s first since May 18, snapping a streak of 81 consecutive games without a three-bagger that sat as the longest such streak by an AL/NL team since at least 1901.

“I got lucky,” said Langeliers, who was unaware of his historic feat until hearing about it postgame. “It kicked really far off the wall, so I got to just keep running.”

For Langeliers, Oakland’s No. 1 prospect and the No. 36 overall prospect in baseball per MLB Pipeline, his performance Sunday was exactly what A’s fans have been anticipating as they watched and heard about his season-long tear through Triple-A. Finishing a homer shy of the cycle, Langeliers turned in a career-high three hits, including a booming double that he scorched at 110.7 mph off the bat in the second, setting the table for a two-run inning.

“It’s great to see the kid having fun,” manager Mark Kotsay said of Langeliers. “For a young catcher who’s stepping into this situation, he’s handled it pretty darn well. He’s got a great attitude. He’s got great passion for the game. Today, he had a great game and contributed to this team’s win.”

All three of Langeliers’ hits registered exit velocities above 97 mph, showing that while there might be some swing-and-miss to his game that remains a work in progress, the 24-year-old catcher’s quality of contact is tantalizing.

Since receiving his first call to the big leagues on Aug. 16, Langeliers is batting .316 with at least one hit in four of his first five games.

“I’m just trying to keep it simple,” Langeliers said of his approach at the plate. “The calmer you can keep your mind just puts you in a better position to succeed at the plate. I’m just trying to start my load early and get myself a chance to recognize and put a good swing on a pitch.”

The multi-dimensional aspect Langeliers brings was on full display. In addition to providing early offense for A’s starter JP Sears, he also supported the rookie left-hander behind the plate. Sears, who the A’s acquired just before the Trade Deadline as part of the return from the Yankees for Frankie Montas and Lou Trivino, continued the positive early returns from the deal by limiting the Mariners to one run on six hits and a walk with three strikeouts over five innings.

“I think it speaks for itself how he’s been playing since he’s been here,” Sears said of Langeliers. “He’s one of the most poised young catchers I’ve ever seen. He definitely has a lot of confidence in himself, but is a really unselfish guy. He gives me confidence. He can run great and throw great. He can really hit. Just an overall great player.”

Langeliers and Sears are among the 15 rookies currently on the A’s active roster who are getting a chance to develop, and they weren’t the only ones who factored into Sunday’s win. Nick Allen contributed an RBI single along with a couple of defensive gems at shortstop, while Cal Stevenson drove home a run with a sacrifice fly in the second.

“They’re getting great experience right now,” Kotsay said of A’s rookies. “Yet today, they played the game like they’ve been here a little bit. That’s what it takes. It takes that confidence and belief. They showed that this series against a playoff-contending team.”