Eduardo Rivera Portland Sea Dogs Pitcher

       
 
Age: 22
Born: June 13, 2003
Birthplace: San Juan, PR
Height: 6-7
Weight: 235
Bats: Left
Throws: Left
   
Drafted: 11th round, 2021 by OAK
How Acquired: Minor league free agent (June 2024)
High School: Colegeio Cadest (PR)

Photo © Kelly O'Connor
Eduardo Rivera photos by Kelly O'Connor
Pronunciation: -
First Pro Contract: July 21, 2021 (OAK)
Signing Scout: Ruben Escalera
Signing Bonus: $125,000
Rule 5 Draft Eligible: December 2025
MLFA Eligible: November 2026
   
Pro Debut: September 21, 2021 (ACL A's)
Added to 40-man: -
MLB Debut: -
Service Time (1/26): 0 days
Options Remaining: 3 (0 used)
Contract (2025): MiLB contract

 
 
 
 
 
     
  Scouting Report & Links      
         
  Physical Description: Tall, extra large frame at 6-foot-7, 275 pounds. Massive frame. Intimidating presence. No remaining projection. Soft body he will have to watch as he gets older.

Mechanics: Throws from a three-quarters arm slot, starting on the first base side of the rubber. No wind-up. Some effort in delivery. Very high leg kick. Short arm action behind and hides the ball there. Quick forward. Average extension. Noticeable head whack and falls off to the third base side. Extremely difficult for left-handed hitters to pick up.

Fastball: 93-97 mph. Tops out at 98 mph. Command and control need work. Below-average command profile. Pitches to the arm side frequently and has to work on being able to locate the pitch glove-side. Pitch jumps on hitters, especially left-handed hitters. Able to hold velocity and often will see it increase as the game goes on. Able to reach back and pitch at the top of the velocity band in key situations. Potential plus offering.

Cutter: 87-89 mph. Short, horizontal break. Primarily used against right-handed hitters. Not a high-usage pitch, but effective when mixed in on occasion either to steal a strike or when ahead in the count as a change of pace. Has shown the ability to bring the pitch over the outside corner against right-handed hitters. Fringe-average potential.

Slider: 83-86 mph. Two-plane shape. Has more vertical break than horizontal. Flashes bat-missing ability when he throws it competitively. Uses against hitters from both sides of the plate. At its best, shows depth and bite. Average potential.

Changeup: 85-89 mph. Has improved as he has thrown it more. Primarily used against right-handed hitters. Struggles to land in the zone, but good at eliciting chases. Pitch has late dive down and away from right-handed hitters. Needs to find more consistency with it, but flashes above-average potential.
  Curveball: 78-80 mph. Throws sparingly, primarily against left-handed hitters. Effective against them with slurvy, 2-to-8 shape that is tough to pick up. Fringe-average potential.

Career Notes: Drafted by Oakland in the tenth round in 2021. Pitched in one game in the Arizona Complex League that season, then missed most of 2022 with an injury. Struggled through control issues in Low-A in 2023. Released by Oakland in May 2024 after 4 games in High-A. Signed with Boston in June 2024 and had a solid showing in the FCL and with Salem. Pitched for Cangrejeros de Santurce in the Puerto Rican Winter League during the 2024-25 off-season and excelled as one of the best pitchers in the league. Re-signed with the organization before becoming a minor league free agent after the 2025 season.

Summation: Potential up-and-down low-leverage reliever who excels against left-handed hitters. Ceiling of a volatile high-leverage reliever or multi-inning bullpen arm. Intriguing arm who has made major strides coming into and during 2025. Has a wide-ranging arsenal with multiple pitches that can miss bats. Has clear plans of attack against right- and left-handed hitters. Fastball, changeup and slider are primary offerings, with cutter and curveball both effective when used in sequence. Changeup has developed considerably this year, but he still needs to find consistency with it to stick in a multi-inning role. Imposing presence on the mound with the stuff to dominate low-minors bats, but inconsistent command and control will be tested in the high minors, where he will not always be able to reach back and overpower hitters. Really impressive find as an in-season minor league free agent with considerable upside if he continues on his current path.

Links

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    Pitching Stats                                          
  year team lg level org age w l era g gs sv ip h r er hr hbp bb so whip k/9 bb/9
2021 ACL Athletics ACL Rk Oak 18 0 0 0.00 1 1 0 1.0 0 0 0 0 0 0 1 0.00 9.00 0.00
2022 ACL Athletics ACL Rk Oak 19 0 0 3.29 8 3 0 13.2 15 7 5 0 0 11 22 1.90 14.49 7.24
2023 Stockton Ports Cal A Oak 20 2 7 5.35 16 12 0 69.0 67 48 41 3 6 44 75 1.61 9.78 5.74
2024 Stockton Ports Cal A Oak 21 0 0 0.00 4 0 2 2.2 1 0 0 0 0 0 3 0.37 10.12 0.00
2024 Lansing Lugnuts Midw A+ Oak 21 0 1 11.88 4 2 0 8.1 11 13 11 0 0 10 8 2.52 8.64 10.80
2024 FCL Red Sox FCL Rk Bos 21 1 1 4.70 4 1 1 7.2 10 6 4 0 0 2 8 1.57 9.39 2.35
2024 Salem Red Sox Car A Bos 21 0 1 1.99 6 4 0 22.2 14 10 5 1 1 7 30 0.93 11.91 2.78
  2024 Cangregeros de Santurce PRWL Wint Bos 21 2 1 1.15 11 7 0 39.0 25 9 5 0 0 12 56 0.95 12.92 2.77
2025 Greenville Drive SAL A+ Bos 22 3 1 1.61 10 6 0 44.2 21 10 8 2 3 16 68 0.83 13.70 3.22
  2025 Portland Sea Dogs East AA Bos 22 1 5 3.40 10 9 0 42.1 34 20 16 2 2 30 40 1.51 8.50 6.38
  2026 Portland Sea Dogs East AA Bos 23     stats                            
   
     
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