ST. PETERSBURG -- Since being acquired from Oakland in a three-team deal in December, Emilio Pagán has been one of the pleasant surprises in the first half of the season for the Rays, establishing himself as one of the key pieces of the bullpen. Behind an uptick in fastball velocity and an improved slider, Pagan entered Tuesday’s game against his former club with a team-leading 0.82 ERA in 20 appearances.

But Tuesday proved to be one of Pagan’s rare off nights. The right-hander allowed back-to-back home runs in the sixth inning as the Rays dropped the second game of the three-game series against the Athletics, 4-3, at Tropicana Field.

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“It was almost shocking with the way his season has gone to this point, but he’ll be fine,” said Rays manager Kevin Cash. “He gave up two home runs to two guys that can hit the ball out of the ballpark.”

Pagan relieved Jalen Beeks, who allowed one run over four innings of work, and immediately retired Marcus Semien to open the inning. It appeared that Pagan had secured the second out of the inning when Matt Chapman grounded out to shortstop, but Willy Adames bounced a throw to first, allowing Chapman to reach on an error.

The right-hander then fell behind in the count against Matt Olson and the A’s first baseman took full advantage, sending a 2-0, 96 mph fastball to the seats in right-center field, giving Oakland a 3-2 lead. Two pitches later, Khris Davis took Pagan deep on a 89 mph slider that stayed in the middle of the plate.

“With Olson, I just got in a bad count,” Pagan said. “I asked Beeks when I got in here and he said he thought it was a good pitch. But when you get into a bad count against a good hitter, he’s going to make you pay.

“And then to Davis, just overthrew a cutter that kind of spun on me and it didn’t really have any depth or action.”

The two home runs are the first Pagan has allowed this season.

Adames, who made the error in the sixth inning, said he didn’t have a good grip on the baseball as he was positioned in the shift. The young shortstop, however, took full responsibility with the throw and said it’s a play he should make.

“I think that was the play that cost us the game,” Adames said. “There would’ve been two outs there and maybe the homers wouldn’t happen, but what can I tell you? I’m a human being and I don’t want to make a mistake.”

“It was just a play that Willy will probably be the first to tell you that we have to get an out on,” Cash added. “But he’s been really, really good for us and that one stung a little bit, but two home runs after that probably magnified it a little bit. That’s the way it goes sometimes. It’s unfortunate.”

The Rays’ offense mounted a late rally in the ninth off Oakland closer Blake Treinen, but the right-hander was able to shut the door, getting Kevin Kiermaier to ground out to first base. Tampa Bay had just four hits on Tuesday and finished 1-for-5 with runners in scoring position.

“We didn’t get the big hit and nothing went our way at the plate,” Cash said. “We’re going to have some days like that. Yesterday we were pretty quiet for five or six innings and then it went our way really well. We’ll bounce back and get back here tomorrow at noon.”