PETERSBURG -- After watching Mike Trout go 6-for-12 with a pair of home runs last week at Angel Stadium, the Rays had the right idea when it came to not letting the Angels’ superstar beat them at Tropicana Field.

“Keep the guys off base in front of him, I think, is what we learned last series. That’s easier said than done,” manager Kevin Cash said Monday afternoon. “He’s good. He’s going to get his hits. You just hope the damage comes when maybe there’s nobody on base. But Mike Trout’s too talented to really hold down.”

The irony was not lost on Cash when Trout came to the plate a few hours later in the exact situation the Rays had hoped to avoid.

With Tampa Bay clinging to a one-run lead in the eighth inning, Trout stepped up with a runner on second base and blasted a go-ahead home run to left field off reliever Phil Maton. Tampa Bay’s struggling bullpen allowed five more runs over the final two innings as the Rays lost the series opener 7-3.

“Look, he's the guy you don't want to come up with guys on base. It's pretty obvious,” Cash said afterward. “But then they just put together a bunch of good at-bats and kind of opened up the game a little bit.”

Maton credited Anthony Rendon for his one-out single in the eighth, saying it was simply “a great piece of hitting on a good pitch” when Rendon slapped a low, 1-2 sweeper to left field. Up came Trout, the likely Hall of Famer whose dominance against the Rays almost defies explanation.

Trout has a career 1.120 OPS against Tampa Bay, the highest mark among all hitters with at least 100 plate appearances against the team. He also owns the best all-time OPS at Tropicana Field, minimum 100 plate appearances, with a 1.109 mark to go along with 10 homers and 19 RBIs in 27 games.

Maton fell behind Trout, 2-1, then tried to bounce a curveball off the plate. But the breaking ball stayed up enough for Trout to hammer it a projected 420 feet, with an exit velocity of 111.6 mph, putting the Angels ahead.

“Tonight we needed a big one at the right time, and he came through,” Angels manager Ron Washington said. “Then it opened it up for everyone else.”

After Trout’s home run, Maton gave up two singles and a walk before Matt Thaiss slapped a bases-clearing double to right field. Those runs bothered Maton even more when Harold Ramírez almost immediately swatted a two-run homer to left in the eighth.

“Trout hitting a homer off you, that happens. It's a big league hitter. The guy's a stud,” Maton said. “But those extra three runs, not having the opportunity to kind of keep us in that ballgame, especially after we scored … it's tough. But ultimately, you've just got to make better pitches.”

It was another tough night for the Rays bullpen, which now owns a Major League-worst 6.92 ERA. Tampa Bay’s relievers have given up the most home runs (14) and walks (46) of any relief corps in the Majors, and their 1.77 WHIP is tied with the Rockies for the highest mark in the Majors.

“It’s not coming easy for them right now. It's tough,” Cash said. “All we can do is continue to give them the ball, continue to support them and trust that they'll get themselves right.”

It was a frustrating finish for the Rays, as they lost for the first time this season when leading after seven innings and wound up with their sixth loss of the season by at least four runs. But the night began in much more promising fashion.

Facing the Angels for the second time in eight days, starter Zach Eflin cruised into the seventh inning with a lead despite minimal support from a lineup that managed just one run out of a bases-loaded, no-out situation in the fifth.

Eflin retired 11 straight batters between a pair of infield singles in the second and sixth and held the Angels scoreless over 6 1/3 efficient innings, then Jason Adam and Tampa Bay’s infield defense finished the seventh. With the bases loaded and one out, Adam got pinch-hitter Mickey Moniak to hit into an inning-ending double play turned by second baseman Curtis Mead and shortstop José Caballero.

“I felt good. Really just following the game plan and was able to keep them off-balance a little bit, had some really good defensive plays out there,” Eflin said. “And Jason coming in and keeping the door shut -- one of those tough ones, but we're going to bounce back.”