2026 Boston Red Sox Top Prospects Ranking

What is there left to say about Tolle at this point? The mustachioed 23-year-old rose from High-A to MLB in his first professional season, skyrocketing up both prospect rankings and the team's starting pitching depth chart. To call his potential tantalizing would be an understatement, particularly if you're dreaming upon a future rotation starring him and fellow southpaw Garrett Crochet.

What he brings to the table — a 6'6" frame, elite extension, and a high-90s fastball — can't be taught. He cruised through his 20 minor-league appearances last year to the tune of a 3.04 ERA and 2.75 FIP while striking out a ridiculous 36.5% of the hitters he faced. Perhaps even more impressively, his walk rate sat at just 6.3%, suggesting a better feel for the strike zone that scouts foretold of the second-round pick.

That dominance led to an earlier-than-expected MLB debut, which generated even more excitement after an electric start against the Pittsburgh Pirates. Unfortunately, he struggled after that point, surrendering nine earned runs over his next 11 innings. It would have been unreasonable to expect him to beat the best hitters in the world right away, but Tolle's specific shortcomings were really exposed in the majors.

His fastball is great, and the raw numbers (96.7 mph average velocity, 28.3% whiff rate, 23.3% put-away rate) are fantastic. But he also used the pitch 64% of the time in his brief big-league stint, hence why hitters were still able to tag it for a .565 slugging percentage and .402 wOBA despite its elite shape and relatively solid command up in the zone. Meanwhile, his cutter and slider both hold very similar shapes and movement profiles, and his changeup is disastrously flat. Tolle only mustered the courage to throw that latter pitch 21 times in the big leagues (all against righties) and it was hammered to the tune of a .711 wOBA.

To put it simply: Tolle throws five pitches, but only one is ready for the major leagues right now. That's why he'll open up the season at Triple-A Worcester. It's also why it wouldn't be a surprise to see him spend all of 2026 there, as he tinkers with his other offerings and learns not to be so reliant on his heater. No pitcher, no matter how good they are, can win with just one pitch. Aroldis Chapman's fastball has always had a slider to pair with; Mariano Rivera's cutter always had a two-seamer or sinker to keep hitters honest.

Tolle has the physical attributes, primary offering, and know-how to be a legitimate frontline starter. In a farm system that also contains Connelly Early, Kyson Witherspoon, and Jake Bennett, he's the best prospect of the bunch. With some refinement of the skills he already he has, Tolle can become the Red Sox's next homegrown ace.

The 2025 season saw the Boston Red Sox's pitching development finally pay off in a big way, as their young pitchers helped get the team through the final month of the season and back into the postseason for the first time since 2021. One of those pitchers was Connelly Early, a 2023 fifth-round draft pick.

Early, who made his MLB debut in September, pitched admirably down the stretch as he made four starts and struck out 29 batters in 19 1/3 innings. He walked just four and allowed five earned runs; his performance led manager Alex Cora to hand him the ball as the starting pitcher in the win-or-go-home game three of the Wild Card series.

Prior to that, Early split 2025 between Portland and Worcester, going 10-3 with a 2.60 ERA in 21 games, 18 of them starts. He threw 100 1/3 innings in that span and struck out 132 batters. Early, who throws from the first-base side of the rubber, has some effort in his delivery but manages to repeat it with a consistent release point. Like most pitchers that the Red Sox have targeted in the past few years, he also has plus extension during his release.

Early relies on a five-pitch arsenal that is made up of a fastball, changeup, slider, curveball and sweeper. His fastball, while averaging just 92-95 mph, topped out at 97 mph and there was an increase in velocity from 2024 that saw the pitch sitting in the low-90s. It has shown more bat-missing ability as he runs up the radar gun, but it's always been designed to help set up his changeup.

That off-speed offering is an above-average pitch thanks to having arm-side run and his low release height. Typically in the mid-80s, he uses a kick-changeup grip and has advanced feel in the pitch, as he throws it often to both left-handed and right-handed batters. When at its best, the pitch will tumble out of the zone, generating whiffs.

His slider averaged 84-87 mph in 2025 and he’s able to land it in the zone. Despite that, it doesn’t miss many bats and is instead used to generate weak contact from opposing batters. His curveball tends to sit in the low-80s at best and has more vertical break. It isn’t consistent, however, sometimes flashing plus movement and other times wobbling toward the plate. Both breakers have above-average qualities but aren't considered in that realm just yet.

His sweeper is his newest pitch, having started working on it in 2024, and it improved as the season went on. It averaged around 80-83 mph and is mainly used against left-handed batters. Much like the curveball, it can show bat-missing ability, but he needs to gain more consistency with it in terms of landing it in and around the strike zone.

Entering the 2026 season, Early is seen as a mid-rotation starter who flashes the upside of a number two or three starter. If he can gain consistency on his three weaker pitchers, that ceiling could rise. The biggest question mark for Early so far is if he can keep the velocity up as he goes deeper into games and across an entire season. The fact he can throw three to four pitches for strikes consistently helps his case in the immediate term.

While many would love to see Early in Boston to open the year, due to their depth the team acquired over the offseason, he is likely headed to Worcester. If the Red Sox keep Early in Worcester for five weeks to open the season, they’ll gain an extra year of control on Early. This would keep him from becoming a free agent until after his age-30 season, something that could change rotation plans down the road. Regardless of where Early starts the season, he’ll be up in Boston as one of the first pitching-related promotions and will end up playing a huge role in how the 2026 season goes down.

When the Red Sox signed Franklin Arias as an international free agent, they did so with the thought of him evolving into a Gold Glove shortstop. Since then, he’s consistently surprised the organization with his ability to put the ball in play, turning himself into a top prospect within the organization. The 2025 season took his outlook to a whole other level.

Playing as a 19-year-old, Arias showcased his abilities out of the gates, opening the season with Salem before becoming one of the youngest players in High-A with Greenville. His performance there allowed him to finish the season with Double-A Portland, roughly 4.5 years younger than the average player. In 116 games between the three levels, Arias hit .278/.335/.388 with 27 doubles, one triple, eight home runs and 66 RBIs, all while playing elite defense at shortstop.

Arias’ ability to make contact is thanks in part to his quick hands and a swing that is line-drive oriented. The young infielder also has great barrel control and a feel for contact. Despite all those positives, however, he does not have the best bat speed and needs to improve his approach at the plate, as he can get too aggressive. Arias has a habit of attacking fastballs early in an at-bat as he tries to hit the ball all over the field. With secondaries, he sometimes has difficulty recognizing the pitch out of a pitcher's hand, leading to high chase rates, though some of that is balanced out by strong in-zone contact skills.

Power-wise, he has meager over-the-fence pop and it’s not a big part of his game. He can, however, produce great exit velocities for his age. Arias is a gap hitter due to his line-drive approach and scouts have described his power as below average.

Speed is also not a big part of his game, as he’s viewed as having below average speed. While he can go first to third on a single or second to home, he will never be viewed as a speed threat. He does make up for his lack of speed with quality baserunning instincts, but he won't derive a lot of his value on the basepaths.

Defense is what Arias is best known for. The infielder is mainly a shortstop but has also seen some time at second base. He has great range and is comfortable playing all angles when charging the ball. He also has the ability to make difficult plays look rather routine. Still just 20 years old, he’s viewed as one of the best middle-infield gloves in all of the minor leagues.

Arias’ value will be determined by how his hit tool continues to develop. Already he’s shown that he can handle shortstop at an elite level, but should his bat not continue to develop, he might peak as a defense-first utility infielder. If his offense continues to improve, he can become a quality starting shortstop despite his lack of power and speed.

Arias will open the season with Portland, where he’ll man the six. In 2025, he only got to play 10 games there and the organization will want to see how he handles a prolonged exposure to higher-level pitching. Given his youth, it wouldn’t be a surprise if he spent the entire season with Portland. If he gets promoted, it would likely be in a similar situation to his schedule last year — a late season showcase against the next minor-league level.