CLEVELAND – The prospect watch has lost another participant. Coby Mayo officially is in the majors.

The Orioles selected Mayo’s contract today from Triple-A Norfolk, filling the one vacancy on the 40-man roster. Livan Soto was optioned as the corresponding move on the active roster, a day after he was recalled and met with the local media.

Mayo was told yesterday to have his passport overnighted, but he didn’t find out officially about his promotion until his removal from last night’s game in Charlotte. He went 4-for-6, came out in the eighth inning and received the news from manager Buck Britton. He boarded a flight this morning to Cleveland.

The move was inevitable for the No. 3 prospect in the system. Mayo, a fourth-round pick in the 2020 draft, was batting .301 with 22 doubles, two triples, 20 home runs, 61 RBIs and a .961 OPS despite missing a month with a rib injury sustained in a collision with a dugout railing.

Injuries pulled Mayo out of the minors. Jorge Mateo has a dislocated left elbow and Jordan Westburg has a fractured right hand, and their absences will extend deep into September. Mayo can play third base, where Westburg made 64 starts this season. He’s another right-handed bat for a team that wanted to correct its imbalance.

CLEVELAND – The Orioles made a series of roster moves this afternoon leading into their four-game series against the Guardians at Progressive Field.

Jordan Westburg was placed on the 10-day injured list with a fractured right hand, and the Orioles recalled Livan Soto from Triple-A Norfolk. Westburg could return by late September. Soto is wearing No. 73.

Outfielder/designated hitter Eloy Jiménez has joined the club after the Orioles acquired him from the White Sox at the deadline and he’s wearing No. 72. Heston Kjerstad was optioned again to Triple-A Norfolk.

Kjerstad is batting .301 with a .998 OPS, 14 doubles and 16 home runs and 58 RBIs in 56 games with Norfolk, but his opportunities remain limited in the majors.

Outfielder Austin Slater, acquired from the Reds, was activated and given No. 15. Reliever Keegan Akin was optioned.

When it comes to O’s infielder Connor Norby, ranked as the club’s No. 5 prospect by MLBPipeline.com and No. 7 via Baseball America, there are differing opinions on his defense.

Baseball America provides Norby a slightly below average 45 grade on the 20-80 scouting scale for his fielding and a 40 for arm. MLBPipeline goes 50 and 50 for both - essentially big league average.

In the early innings Saturday, Norby looked like a plus defender.

He made a fantastic play in the first inning Saturday. He ranged up the middle sliding onto the outfield to field a Manny Machado grounder and then he got a lot on the throw from the seat of his pants for the out. Two innings later he made another nice play and cut down a runner at home with an off balance throw with the infield in.

There was nothing below average about those plays. Both were big and provided a chance for Norby to show he has improved a lot with his second-base defense.

We have seen the Orioles go 20-9 this year versus the American League East. We have seen them produce nine straight winning months, the longest current active streak in the majors. Since the start of 2023, Baltimore is 162-102 (.614), and that is the best win percentage in the majors in that span.

In the span of four series in June we saw the Orioles sweep four in a row at Tampa Bay and win consecutive series against Atlanta, Philadelphia and the New York Yankees.

But since they capped that four-series run by beating the Yankees 17-5, it has turned for the worse. And the Orioles can't seem to turn it back.

Since June 21 they look nothing like a playoff team. They have two five-game losing streaks in this stretch and in their most recent five games, they are 1-4.

That is a mark of 12-17 and a -41 run differential since that June day.

The Orioles traded for another starting pitcher and might not be done. The rotation was targeted as an area of need. Surgeries and struggles left them no choice.

Grayson Rodriguez wanted to provide the latest example that the top portion is in good hands, and he did it for a while. Corbin Burnes registered his 17^th quality start yesterday in Miami and Rodriguez carried a shutout into the sixth tonight, but Jurickson Profar hit a game-tying, two-run homer and manager Brandon Hyde went to his bullpen.

Another area that's under some construction.

Burnes and Rodriguez remain a formidable one-two punch, but the Orioles had to get off the canvas again like they did yesterday in extras. They managed it briefly and went down again, this time unable to scramble back to their feet.

The defense let down reliever Burch Smith in the sixth. The Orioles tied the game in the eighth, but Craig Kimbrel surrendered a two-run homer to Profar with two outs in the ninth in the Orioles’ 6-4 loss to the Padres before an announced sellout crowd of 43,692 at Camden Yards.

The trade deadline doesn’t arrive until Tuesday at 6 p.m., but the Orioles got aggressive today. They found the opportunities to strike and didn’t let them pass.

They latched onto a starter under team control beyond 2024 who didn’t cost one of their top prospects. They strengthened their bullpen and added a plus defender for the outfield.

The total cost was outfielder Austin Hays and minor leaguers Jackson Baumeister, Mac Horvath and Matthew Etzel.

Hays went to the Phillies for reliever Seranthony Domínguez and outfielder Cristian Pache. The Orioles later announced that they acquired Zach Eflin from the Rays.

Eflin will report this weekend. Domínguez and Pache arrived at Camden Yards this afternoon.

With all the speculation that the O’s might be trading some prospects at the trade deadline and amid recent reports via ESPN that the club might be willing to deal Ryan Mountcastle and Cedric Mullins, it was another long-time O's player leaving the club.

Austin Hays, a veteran of 557 games over parts of seven seasons with the Orioles, was dealt to the Philadelphia Phillies.

The return was right-handed reliever Seranthony Domínguez and outfielder Cristian Pache.

Domínguez, 29, provides help for the Baltimore bullpen, which allowed late-game runs the last two days at Miami.

Domínguez is 3-2 with a 4.75 ERA and 1.222 WHIP on the year over 36 innings. Over the last three seasons, since 2022, he has a 3.74 ERA and 1.256 WHIP.

The Orioles made a significant change to their outfield, surrendering one of their longest tenured players, and fortified the bullpen earlier today by consummating their first trade approaching Tuesday’s deadline.

Austin Hays was dealt to the Phillies for reliever Seranthony Domínguez and outfielder Cristian Pache. Minor league pitcher Levi Stoudt was designated for assignment to make room on the 40-man roster.

Hays was a third-round pick in the 2016 draft out of Jacksonville University who made his major league debut the following September and started in last year’s All-Star Game. He’s battled injuries throughout much of his career and played in 63 games this season, slashing .255/.316/.395 with 13 doubles, three home runs and 14 RBIs in 175 plate appearances.

The part-time role was a tough adjustment for Hays, who played in 557 games with the Orioles over parts of seven seasons, but Colton Cowser’s emergence as a regular and the shuffling with Heston Kjerstad and Kyle Stowers limited his opportunities.

The Phillies might platoon Hays with Brandon Marsh before he enters his final year of arbitration eligibility.