Which prospect did Red Sox trade to Athletics for Rule 5 pick Ryan Watson?

Following the conclusion of Wednesday’s Rule 5 Draft, the Red Sox swung a trade with the Athletics for a pitcher who had just heard his name called.

In exchange for right-hander Ryan Watson, whom the Athletics took from the Giants system with the eighth overall pick in the major league phase, the Red Sox sent infield/outfield prospect Justin Riemer and cash considerations to the A’s.

MassLive.com’s Chris Cotillo was the first to report news of the trade.

Riemer, who turns 24 in February, was not ranked among Boston’s top 60 prospects by SoxProspects.com. The Virginia native was originally selected by the Red Sox out of Wright State with the 133rd overall pick in the 2023 draft, which the club received as compensation for losing Nathan Eovaldi to the Rangers in free agency the previous winter. He received an above-slot $500,000 signing bonus but was recovering from a torn ACL at that time, which pushed his professional debut back until last July.

After splitting the remainder of the 2024 season between the Florida Complex League and High-A Greenville, Riemer spent the majority of 2025 with the latter affiliate. Though he was sidelined from April 16 to May 15 with a shoulder injury, the right-handed hitter batted .232/.423/.275 with six doubles, one home run, 16 RBIs, 33 runs scored, nine stolen bases, 64 walks, and 55 strikeouts in 76 games (279 plate appearances) for the Drive. He appeared in six games (August 23-24, September 10-14) across two separate stints with Double-A Portland as well, going 4-for-18 (.222) with one double, two RBIs, five runs scored, five walks, and five strikeouts.

Overall, Riemer slashed .231/.421/.276 with seven doubles, one home run, 18 RBIs, 38 runs scored, nine stolen bases, 69 walks, and 60 strikeouts in 82 total games (303 plate appearances) between Greenville and Portland this past season. Among 36 Red Sox minor leaguers who made at least 300 trips to the plate, Riemer ranked first in walk rate (22.8 percent), on-base percentage, and swinging-strike rate (3.2 percent), fourth in wRC+ (123), seventh in wOBA (.360), and ninth in strikeout rate (19.8 percent), per FanGraphs.

On the other side of the ball, Riemer saw playing time at five different positions between his stops in Greenville and Portland this year. The versatile 5-foot-10, 170-pounder logged 309 innings at second base, 179 innings at third base, 108 innings in left field, 40 innings in right field, and 14 innings at shortstop, committing eight errors in 299 total defensive chances. He also made three starts at DH.

Though he has yet to hit for much power to this point in his career, Riemer has drawn praise for his advanced approach, pitch recognition, and bat-to-ball skills. Those traits, among others, must have stood out to the Athletics when putting together this one-for-one swap with the Red Sox.

With that being said, Riemer — barring another move — seems likely to open the 2026 season with either the Athletics’ High-A or Double-A affiliate. It is worth noting that he is in line to become eligible for the Rule 5 Draft for the first time next winter.

(Picture of Justin Riemer: Kelly O’Connor/sittingstill.smugmug.com)

Red Sox promote IF/OF prospect Justin Riemer (.423 OBP) to Double-A Portland

The Red Sox have promoted infield/outfield prospect Justin Riemer from High-A Greenville to Double-A Portland, according to the club’s MiLB.com transactions log.

Riemer is not currently regarded among Boston’s top prospects by publications like Baseball America, MLB Pipeline, or SoxProspects.com. The 23-year-old has not hit for much power this season, though he has gotten on base at an exceptional rate thus far.

After breaking camp with Greenville earlier this spring, Riemer suffered a shoulder injury on April 15 and was sidelined for a month as a result. The right-handed hitter returned to action on May 15 and batted .243/.423/.287 with five doubles, one home run, 16 RBIs, 26 runs scored, nine stolen bases, 54 walks, and 45 strikeouts in 66 games (241 plate appearances) for the Drive overall. That includes a .238/.365/.286 slash line against lefties and a .245/.439/.288 slash line against righties.

Among the 95 hitters who entered play Friday having made at least 240 trips to the plate in the South Atlantic League this year, Riemer ranked first in walk rate (22.4 percent) and swinging-strike rate (2.8 percent), second in on-base percentage, 14th in wOBA (.364), 15th in strikeout rate (18.7 percent), 16th in wRC+ (127), and 34th in batting average and OPS (.710), per FanGraphs.

Defensively, Riemer has seen playing time at five different positions so far this season. In addition to making 34 starts at second base, nine starts at third base, and two starts at shortstop, the versatile 5-foot-10, 170-pounder was introduced to the outfield in early June and has since logged 125 error-free innings between the two corner spots. He has also made three starts at DH.

Riemer was originally selected by the Red Sox with the 133rd overall pick (which the club received as compensation for qualified free agent Nathan Eovaldi signing with the Rangers in December 2022) in the 2023 draft out of Wright State. The Virginia native signed with Boston for an over-slot $500,000 shortly thereafter, but was still recovering from a torn ACL he suffered that spring, which pushed his professional debut back until last July.

In the time since officially entering the pro ranks, Riemer has drawn praise for his disciplined approach, pitch recognition, and bat-to-ball skills. As noted in his SoxProspects.com scouting report, though, Riemer’s ability to draw walks at a high rate could be put to the test as he moves from the lower minors to the upper minors, where he is sure to be challenged more by tougher opposing pitchers.

Having said that, Riemer is not in the starting lineup for Portland’s game against Binghamton at Hadlock Field on Friday night.

(Picture of Justin Riemer: Kelly O’Connor/sittingstill.smugmug.com)

How did Red Sox prospect Justin Riemer fare in long-awaited pro debut this season?

After losing qualified free agent Nathan Eovaldi to the Rangers in December 2022, the Red Sox received a compensatory pick that fell between the fourth and fifth rounds of the 2023 amateur draft.

With that pick at No. 133 overall last July, the Red Sox selected Wright State infielder Justin Riemer, who was roughly four months removed from suffering a torn ACL in early March that cost him most of his redshirt sophomore season. As such, the Virginia native signed with Boston for $500,000 but did not make his professional debut until this summer.

Having expended much of last winter and this spring rehabbing in Fort Myers, Riemer opened the 2024 campaign on the 60-day injured list and later began a rehab assignment with the Florida Complex League Red Sox on July 11. The right-handed hitting 22-year-old spent two weeks with the rookie-level affiliate, batting .296/.462/.407 with one double, one triple, four RBIs, six runs scored, one stolen base, 10 walks, and five strikeouts in 10 games (39 plate appearances). He was then activated and assigned to High-A Greenville, meaning he would skip Low-A Salem, on July 27.

In his next 28 games for the Drive, Riemer slashed .240/.397/.280 with four doubles, three RBIs, 21 runs scored, eight stolen bases, 19 walks, and 24 strikeouts over 126 plate appearances. Among the 180 hitters who made at least 120 trips to the plate in the South Atlantic League this year, Riemer ranked second in swinging-strike rate (4.1 percent), 12th in on-base percentage, 21st in walk rate (15.1 percent), 29th in strikeout rate (19 percent), 64th in wOBA (.343) and wRC+ (113), and 76th in batting average, per FanGraphs.

Altogether, Riemer produced a .252/.412/.307 line with five doubles, one triple, seven RBIs, 27 runs scored, nine stolen bases, 29 walks, and 29 strikeouts in 38 total games (165 plate appearances) between the FCL and Greenville to cap off his first pro season. At those two stops, the 6-foot, 170-pounder split his playing time between both middle infield positions. He committed five errors in 65 chances across 20 starts (174 innings) at shortstop and two errors in 42 chances across 14 starts (109 innings) at second base.

Riemer, who turns 23 in February, is currently regarded by SoxProspects.com as the No. 36 prospect in Boston’s farm system. While power is not a major part of his game at the moment, he does possess intriguing bat-to-ball skills and solid instincts in the field. Barring a trade or other surprise move this winter, he is projected to return to Greenville for the start of the 2025 season.

(Picture of Justin Riemer: Gwinn Davis/Greenville Drive)

Red Sox draft Wright State shortstop Justin Riemer with compensation pick for Nathan Eovaldi

The Red Sox have selected Wright state shortstop Justin Riemer with the 133rd overall pick in the 2023 MLB Draft. Boston received that pick as compensation for extending a qualifying offer to and then losing longtime starter Nathan Eovaldi to the Rangers in free agency over the winter.

Riemer was taken back-to-back with Georgia Tech shortstop Kristian Campbell in between the fourth and fifth rounds of the draft. The switch-hitting 21-year-old tore his ACL in early March and saw his stock drop.

Prior to suffering the season-ending knee injury, though, Riemer had gotten his redshirt sophomore campaign off to a strong start, batting .323/.563/.645 with one double, three home runs, seven RBIs, 12 runs scored three stolen bases, 15 walks, and just two strikeouts in his first 12 games (48 plate appearances) for the Raiders.

In 2022, Riemer was named to the Horizon League All-Freshman Team and Horizon League All-Tournament Team after slashing .329/.454/.459 with two homers and 27 RBIs across 44 games (185 plate appearances) in his debut season with Wright State.

Defensively, Riemer has experience at both middle infield positions. Last season, for instance, the 6-foot, 170-pounder out of Arlington, Va. made 30 appearances at second base and 16 appearances at shortstop.

“I love playing both spots and the responsibility that comes with playing both spots,” Riemer told the Baseball Prospect Journal’s Dan Zielinski III back in March. “I’m really comfortable at both for different reasons, but I love the middle infield.”

As noted by Zielinski III, Riemer is well-regarded for his elite bat-to-ball skills as well as a sound approach at the plate in which he rarely expands the strike zone. He also has the ability to consistently square up baseballs from the right side — his natural side — of the plate.

“My biggest strengths right now are my bat-to-ball skills and plate discipline,” Riemer said. “They are things I take very seriously and something I knew I did a good job on last year, given my strikeout percentage. I can play it to my advantage, and I worked on it this offseason to do even better.”

Riemer, who does not turn 22 until next February, is the fifth position player taken by Boston within the club’s first six picks. The 133rd overall selection in this year’s draft comes with a slot value of $487,800.

(Picture of Justin Riemer: Wright State University Athletics)