Adley Rutschman is becoming Mr. Seventh Inning.

For the third time in five games, the switch-hitting sophomore roped a go-ahead, two-RBI double in the seventh to rescue the Oregon State baseball team. Tuesday night’s two-bagger — a screaming shot to the wall in right — put the second-ranked Beavers back on top of visiting Portland.

OSU (13-0) tacked on an insurance run in the eighth for a 6-3 victory in front of 3,136 fans at Goss Stadium.

“He’s certainly been giving us great at-bats, and he’s been doing it all year long,” coach Pat Casey said. “He’s really improved and worked so hard to become a good hitter on both sides of the plate, and it’s good to see him reap the rewards.”

Rutschman caught all nine innings and finished 2 for 4 against the Pilots (4-8).

In last weekend’s nonconference series with Hartford, Rutschman also had go-ahead doubles in Games 1 and 3. The last two drives have come from the left side.

“I’m just fortunate enough to get in those situations and get a good pitch to hit,” said Rutschman, who strives to keep the same approach at the plate in high-leverage situations. “I try to be as consistent as possible. Just being able to get a pitch to hit and taking advantage of that is important in any situation, but obviously there you have to step up a little bit more.”

Trevor Larnach launched a three-run homer in the first inning for the Beavers, who will host Cal State Fullerton for a much-anticipated three-game series this weekend. Friday’s opener is set for a 5:35 p.m. first pitch.

Brandon Eisert (2-0) pitched 3⅓ innings of scoreless, hitless relief with no walks and six strikeouts to get the win.

The sophomore left-hander also flummoxed the Pilots a season ago, striking out a career-high nine in a 4-3 victory last April.

“His fastball was working for him, and then he was able to compliment it with the changeup,” Rutschman said. “He comes from kind of a weird arm slot where he hides the ball so it gets on guys real fast, and I know from personal experience. … And then when he throws a changeup in there, it really messes with hitters.”

Christian Chamberlain was effective in his first college start, allowing just one hit with one walk while striking out four in four scoreless innings. The freshman lefty exited after 61 pitches and did not factor into the decision.

Locked in a 3-3 tie, Tyler Malone led off the seventh with a single and Steven Kwan later walked to put runners on first and second with one out. After Kwan and pinch-runner Kyler McMahan moved up on a Cadyn Grenier groundout, Rutschman crushed a 1-0 pitch from reliever Connor Knutson to clear the bases.

One inning later, Andy Armstrong drove in Jack Anderson with a single to left that put OSU up 6-3.

Jake Mulholland pitched a 1-2-3 ninth for his fourth save of the year.

Knutson (0-1) was the hard-luck loser, giving up two runs on three hits with six strikeouts and three walks in 4⅔ innings. The sophomore righty kept Portland in the game after a rough outing from starter Jake Hawken.

Larnach belted his team-leading sixth homer of the year against Hawken, a senior righty. The junior outfielder’s drive landed in the top row of the bleachers in right-center, plating Grenier and Rutschman for a 3-0 lead.

“It was middle of the plate and I was ready to hit,” Larnach said of the 0-0 pitch. “So I got what I was looking for and took advantage.”

Larnach was feast or famine against Hartford, finishing just 2 for 17 with five strikeouts while collecting a two-RBI double and a grand slam.

Portland broke through in the fifth with consecutive RBI doubles from Matt Kelly and Beau Brundage, the son of former OSU great Dave Brundage. The younger Brundage then scored on an Eisert wild pitch to tie the game.

All three runs were charged to Sam Tweedt, who lasted just two thirds of an inning.

OSU has now won 22 straight home games, the longest active streak in the country, dating back to 2017. The Beavers entered Tuesday as one of five unbeaten teams in all of Division I.