For six innings on Thursday afternoon, the Rays took a glimpse into the bright future of their pitching staff. Left-hander Shane McClanahan unleashed some overpowering stuff in his regular-season debut, and righty Luis Patiño followed with two scoreless innings out of the bullpen.

But the two top pitching prospects couldn’t outshine the current gloomy state of Tampa Bay’s lineup, and Oakland took advantage in the ninth inning. Matt Chapman hit a line-drive double off Diego Castillo and over Brett Phillips’ outstretched glove in right field, Jed Lowrie scored from first when Phillips yanked the throw home, and the A’s held on to deal the Rays a 3-2 defeat at Tropicana Field.

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The Rays’ offensive struggles continued as they managed only five hits and went 0-for-6 with runners in scoring position. They have only two hits in their last 44 at-bats with runners in scoring position.

“Hopefully we're going to stop talking about this soon. I think we will. But the offense is just having a rough go right now,” manager Kevin Cash said. “We've been pitched well, pitched tough. Saying that, we've got a good offense, and we're just in a little bit of a rut that we've got to find a way to get out.

“We’re going to start giving our pitchers a little bit of support here. We’ve asked a lot of our pitchers, some young ones, and they’ve really come up in a big way for us and just kept us in every single ballgame.”

That was the case again on Thursday thanks to a solid start from McClanahan and two innings of quality relief work from both Patiño and Andrew Kittredge.

After making his Major League debut in the postseason last year, McClanahan came out hot in his first big league start in front of family and Billy Mohl, his coach at the University of South Florida, the day after his 24th birthday.

“I was more nervous before the game than actually being on the mound,” McClanahan said. “It's like, once you're on the mound, everything just kind of takes care of itself and you actually get to do what you want to do.”

McClanahan struck out A’s leadoff man Mark Canha with a nasty 100.5 mph fastball with noticeable arm-side run, then he got Ramón Laureano swinging on a 93 mph slider -- a pitch McClanahan developed over the offseason. He struck out four of the first seven hitters he faced while inducing 10 swinging strikes in the first two innings.

“I thought he was outstanding,” Cash said. “Just really, really impressive to watch from the side. The stuff speaks for itself.”

Oakland gave McClanahan, Tampa Bay’s No. 5 prospect, a little bit of trouble in the third. Tony Kemp and Canha strung together back-to-back singles around a wild pitch, although a 95.9 mph throw from Phillips -- the second-fastest outfield assist in the Majors this season -- cut down Kemp at the plate. But Laureano then smacked a double to left field, the A’s third straight hit, to tie the game.

McClanahan gave up another run in the fourth, leaving a two-strike changeup over the plate to Chapman, who launched it over the left-field wall. In hindsight, McClanahan said that he probably should have thrown a slider or curveball. But he thought a changeup would have finished off a pitch sequence that started curveball-slider-fastball, and he was more frustrated with the changeup’s middle-middle location.

But it was an encouraging start overall for McClanahan, who threw 59 pitches (42 strikes) and struck out five while inducing 15 swinging strikes in four innings. Brandon Lowe took McClanahan off the hook when he crushed his fourth home run of the season out to right-center field in the fifth inning off of A’s righty Chris Bassitt.

“I felt fine. I made some good pitches, made some mistakes, and obviously it's a good starting point to work forward from,” McClanahan said. “Obviously, I want to win, and this entire team wants to win. So there's a lot to go forward on and just make some improvements.”

Patiño took over after that, striking out two while allowing just one hit as he threw 43 pitches (29 strikes) in two innings. The 21-year-old, the club’s No. 2 prospect according to MLB Pipeline, made his Rays debut as a multi-inning opener on Sunday vs. the Blue Jays.

“McClanahan was super efficient with his pitches, whereas Patiño, they worked him for some at-bats. But he got out of it and just continued to make pitches,” Cash said. “Very encouraged with both those guys.”

Kittredge held the line after that, and then the Rays gave the ball to Castillo in the ninth. Working for the third day in a row, Castillo struck out Laureano before walking Lowrie on four pitches. After retiring Sean Murphy for the second out, Castillo gave up the game-winning double to Chapman that Phillips said he should have caught.

“I'm always gonna give 100 percent, try and do what I can for these pitchers,” Phillips said. “It's frustrating because I know deep down that [if] we have that same play 10 more times, I catch it 10 times. So, of course it's that one that affects the outcome of a game.”