Red Sox to promote pitching prospects Payton Tolle, Eduardo Rivera to Double-A Portland

The Red Sox are promoting pitching prospects Payton Tolle and Eduardo Rivera from High-A Greenville to Double-A Portland, as was first reported by Josh Ball of Beyond the Monster.

Tolle and Rivera, both 22, are in their first full seasons as members of the Red Sox organization. The pair of large left-handers opened the 2025 campaign with Greenville and excelled there, making the club’s decision to elevate them to Portland at this time hardly surprising.

Tolle was selected by the Red Sox with the 50th overall pick in last summer’s draft out of TCU. The Oklahoma native received an above-slot $2 million signing bonus but did not make his professional debut (in which he made the jump straight to Greenville) until April after logging 81 1/3 innings in his junior season with the Horned Frogs.

In 11 outings (10 starts) for Greenville, Tolle posted a 3.62 ERA (2.89 FIP) with 79 strikeouts to 14 walks over 49 2/3 innings in which opposing hitters batted .234 against him. He capped off his time with the Drive by allowing just one earned run on five hits, one walk, and nine strikeouts across six quality innings against Greensboro on Sunday. Of the 83 pitches he threw, 55 were strikes and 21 generated a swing-and-miss.

Among the 38 pitchers who have thrown at least 45 innings in the South Atlantic League this season, Tolle ranks first in strikeouts per nine innings (14.32), strikeout rate (38.3 percent), and swinging-strike rate (17.3 percent), second in xFIP (2.50), fourth in FIP, 13th in walks per nine innings (2.54), walk rate (6.8 percent), and WHIP (1.17), and 19th in batting average against, per FanGraphs.

Tolle, who turns 23 in November, is currently regarded by Baseball America as the No. 4 prospect (first among pitchers) in Boston’s farm system and the No. 84 prospect in the sport. The 6-foot-6, 250-pound southpaw throws from a three-quarters arm slot and operates with a four-pitch mix that consists of a 93-96 mph fastball (reached 97.7 mph on Sunday), a 90-92 mph cutter, an 84-88 mph sweeping slider, and an 87-90 mph changeup, as noted in his SoxProspects.com scouting report.

Rivera, meanwhile, is further into his professional career than Tolle. The native Puerto Rican was originally selected by the Athletics in the 11th round (338th overall) of the 2021 draft out of high school and was released last May. He quickly latched on with the Red Sox as a minor-league free agent and split the remainder of the 2024 season between the Florida Complex League and Low-A Salem, forging a 2.67 ERA (2.55 FIP) with 38 strikeouts to nine walks over 30 1/3 total innings.

After putting together a strong showing in the Puerto Rican Winter League, Rivera has undoubtedly been one of the biggest surprises on the pitching side of things for Greenville this season. He compiled a 1.61 ERA (2.35 FIP) with 68 strikeouts to 16 walks across 10 outings (six starts) spanning 44 2/3 innings in which he held opposing hitters to a .138 batting average. Like Tolle, he ended his time with the Drive by yielding just one earned run on five hits, no walks, and eight strikeouts over 6 1/3 innings against Greensboro this past Friday. Of the 87 pitches he threw, 60 landed for strikes and 17 were whiff-inducing.

Among the 49 pitchers who have thrown at least 40 innings in the South Atlantic League this year, Rivera ranks first in strikeout rate (39.5 percent), swinging-strike rate (18.8 percent), groundball rate (59 percent), batting average against, second in ERA, FIP, and xFIP (2.42), third in strikeouts per nine innings (13.70) and WHIP (0.83), and 24th in walks per nine innings (3.22), per FanGraphs.

Rivera, who just turned 23 earlier this month, is not currently ranked by Baseball America but is regarded by SoxProspects.com as Boston’s No. 35 prospect, which places 17th among pitchers in the organization. As noted in his SoxProspects.com scouting report, the 6-foot-7, 235-pound hurler throws from a three-quarters arm slot and features a 93-97 mph fastball (reached 96.2 mph in Friday’s start), an 87-89 mph cutter, an 83-86 mph slider, an 85-89 mph changeup, and a 78-80 mph curveball.

Both Tolle and Rivera are now slated to join a talented Portland pitching staff that already includes the likes of David Sandlin, Connelly Early, and Hayden Mullins, among others. The Sea Dogs open a six-game series on the road against the Binghamton Rumble Ponies on Tuesday.

With the promotions of Tolle and Rivera, fellow lefty Shea Sprague is once again being elevated from Salem to Greenville, according to SoxProspects.com’s Chris Hatfield. Sprague, a Hanover, Mass. native, made one relief appearance for the Drive in late May in which he struck out five and walked only one over 3 1/3 scoreless, one-hit frames before being sent back down on June 3.