By 6 p.m. Friday, the Orioles must decide which prospects they’ll add to the 40-man roster. If they’re added, they’ll be exempt from the Rule 5 draft on December 10th.

The 40-man roster is at 35 going into Friday, so the Orioles can add five players without taking anyone off the list. They could add more, but they probably won’t.

A year ago, their 40-man roster was weaker, and they added four players — pitchers Keegan Akin and Dean Kremer, first baseman/outfielder Ryan Mountcastle and outfielder Ryan McKenna.

They didn’t know that there wouldn’t be a minor league season at the time, or that the major league season would consist of 60 games. It seemed possible that all four would play in the majors in 2020.

It turned out that Akin, Kremer and Mountcastle played for the Orioles, but not as long as they might have in a 162-game season.

Akin was the first of the three to join the Orioles, getting recalled on August 8th. He didn’t make his debut until August 14th and made a couple of trips back to the alternate training site in Bowie before returning to stay on August 30th.

By then, Mountcastle was with the Orioles. He was recalled on August 21st when Chris Davis went on the 10-day injured list because of tendinitis in his left knee.

On September 6th, Kremer was recalled, and the three showed promise as they spent the final three weeks of the season together. They were joined by left-hander Bruce Zimmermann, who was recalled on September 17th.

Had Zimmermann not been brought up, he would have been added to the 40-man roster on Friday.

McKenna was at the alternate site for the summer, but he did make the final two road trips as part of the team’s taxi squad.

Yusniel Diaz is a certainty to be added. The 24-year-old outfielder could have played for the Orioles in 2020 had there been a full minor league season.

After he was acquired from the Los Angeles Dodgers in the Manny Machado trade in July 2018, Diaz was sent to Double-A Bowie. He stayed there in 2019, and while the Orioles could have recalled him late in 2020, they didn’t.

With Mountcastle, Austin Hays, Cedric Mullins and DJ Stewart sharing playing time in the outfield, there wasn’t room for Diaz—even after rightfielder Anthony Santander suffered a season-ending oblique injury on September 4th.

The Orioles wanted to see Diaz play in Triple-A for the first time in 2020. It seems unlikely that Diaz would start 2021 with the Orioles because they still want to see him at Triple-A, whenever the minor league season begins.

Two pitchers, right-hander Michael Baumann and left-hander Zac Lowther, also seem certain to be added.

Baumann, a college classmate of Hays at Jacksonville University, hasn’t pitched in Triple-A and his time at the alternate site ended early because of a flexor strain in his right arm.

Neither Baumann, 25, nor Lowther, 24, who had an oblique injury and spent limited time at Bowie, has pitched above Double-A.

If the Orioles add a fourth player, it could be right-handed pitcher Isaac Mattson, who was one of four pitchers acquired from the Los Angeles Angels for Dylan Bundy in December 2019.

Mattson, a 25-year-old right-hander, pitched in five Triple-A games for the Angels’ team in Salt Lake in 2019 and was also at the alternate site. After the Orioles included him in the 60-man player pool, it would seem logical that they would want to keep him.

If the Orioles decide to fill out the 40-man roster, they could add infielder Rylan Bannon. However, he plays second and third base, and it seems that teams prefer utility infielders who play shortstop. The guess here is that Bannon won’t be protected and won’t be claimed in the Rule 5 draft.

Bannon has Triple-A experience and it wouldn’t be a shock if he began 2021 with the Orioles, or at least joined them early in the season. It also seems unlikely that the team will protect utility infielder Mason McCoy, who could play second or short. While Bannon was a late add to the 60-man player pool, McCoy wasn’t.

The Orioles have utility infielder Ramón Urias on the 40-man roster.

Right-handed pitcher Zach Pop, who hasn’t pitched since Tommy John surgery in May 2019, is a long shot to be protected. Along with Bannon, Diaz and Kremer, he came from the Dodgers, and although his arm is intriguing, a team would have to keep him on the roster for at least 90 days in 2021. Pop might see time with the Orioles in 2021 but might be too big a risk for another team to draft.

Cody Sedlock, who was the team’s No. 1 draft pick in 2016, wasn’t protected last year, wasn’t selected and wasn’t part of the 60-man player pool.

Australian left-hander Alexander Wells has a 2.82 ERA in four minor league seasons, but he wasn’t at the alternate site, either.

It seems unlikely that either Sedlock or Wells, who haven’t pitched above Double-A, will be protected or drafted.