BALTIMORE -- For the Orioles, the final four weeks of the season will be about the continued development of their key young players as they build on the gains they’ve accrued at the big league level. In that light, keep an eye on Ryan Mountcastle.

Mountcastle might still be a dark horse in the American League Rookie of the Year race. But he has the Orioles’ rookie home run record in his sights after socking his 24th as part of a four-hit game Sunday afternoon, providing a highlight in Baltimore’s 12-8 series-finale loss to the Rays. The third-inning solo shot put Mountcastle four back of Cal Ripken Jr.’s club record from 1982 with 33 games to play.

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That would seem to be attainable for Mountcastle given the way he has swung the bat for weeks now. Producing an OPS of .956 since the All-Star break, Mountcastle is approaching the end of August having batted .355 with seven homers this month. His .496 slugging percentage would be the highest by a rookie in Orioles history.

The Orioles did get to say goodbye to the Rays until 2022, and for that they must be grateful. Their loss Sunday dropped them to 1-18 against Tampa Bay, making them the third team in the divisional era to lose 18 games to one opponent in a season. The latest was charged to right-hander Spenser Watkins, who allowed three homers en route to his seventh consecutive loss. He is the third Oriole since 1994 to lose seven straight starts. Watkins was optioned to Triple-A Norfolk after the game.

“You want to go out there and win every day,” Mountcastle said. “But I just need to keep working hard. We’re all going to keep pounding away for the rest of the season, and hopefully get more wins down the stretch here.”

Win or lose, it’s production that is sure to garner Mountcastle some attention in a crowded AL Rookie of the Year Award field that includes Rays outfielder Randy Arozarena, Rangers outfielder Adolis García and Astros righty Luis Garcia. Mountcastle’s defense and low OBP drag his candidacy down a bit, but few have been more productive: He ranks second among AL rookies in homers, RBIs and slugging, and third in runs, hits and doubles.

“He’s swinging the bat great,” said Orioles manager Brandon Hyde. “Mounty has a ton of ability and is going to be a good player in this league.”

Mountcastle would likely rank higher if not for Arozarena’s season-long campaign against Orioles pitching. Arozarena hit safely in all 13 games he played against Baltimore, and he finished the season series 26-for-58 (.448) with four doubles, eight homers and 19 RBIs.

Tampa Bay blues
It’s not easy losing 18 of 19 to an opponent. The Orioles are the third team in the divisional era (since 1969) to do it, after the Tigers against the Indians and the Mariners against the Astros in 2019.

“They are extremely sound,” said Watkins. “They take really good at-bats 1 through 9. There really isn’t much of a breather there. They have a plan and stick to that plan. They are a very tough lineup to face, absolutely. They are consistently coming after you.”

The Orioles were outscored by 79 runs (150-71) against Tampa Bay. They are the fourth team since 1960 to allow 150 runs to one opponent. Baltimore also did it in ‘17 and ‘19 against the Yankees.

The Orioles’ only win vs. the Rays this year was a 6-1 triumph on July 19, and they lost all nine meetings at Camden Yards. Several of their losses in recent weeks involved Paul Fry, who loaded the bases before allowing Joey Wendle’s seventh-inning grand slam Sunday. That was Tampa Bay’s fourth grand slam against Baltimore this season, an O’s record by one opponent.

“You can understand what they're going through,” Rays manager Kevin Cash said. “That team over there plays hard all the time.”

Fry’s numbers against the Rays are especially eye-popping: 18 earned runs across 4 2/3 innings in nine appearances, five of which came in August. He has seen his ERA soar from 3.64 to 6.08 in that span. Fry was optioned to Norfolk after the game.

Hip, hip, Jor-ge!
As the Orioles look to identify pieces for 2022, it’s hard to ignore the impact Jorge Mateo has had since joining the club on Aug. 5. He has notched 24 hits in 19 games since, including his long two-run home run Sunday, his first with the team. He has also stolen four bases and posted an .895 OPS while playing five positions.

“He’s getting an opportunity here. It’s probably something he’s been waiting for for a while,” Hyde said. “We’re going to continue to give it to him because he’s super athletic. You saw the power today. He obviously has a ton of speed. There is a lot to like. I like the way he’s playing the game, and happy he’s taking advantage of the opportunity we’re giving him.”