Pittsburgh Pirates shortstop Konnor Griffin. Sam Navarro-Imagn Images

Four rookies poised to have breakout MLB seasons

By Daniel Morrison | Last updated Mar 26, 2026 1:10 PM ET

The MLB season is already here. With that, the old guard of stars is returning to the field, but they'll have plenty of company from a youth movement that is taking over baseball.

With the calendar yet to turn over to April, here's a look at some of the rookies who are worth keeping an eye on. These are four of the players who hope to be well-known names by the time October baseball rolls around.

1. Kevin McGonigle, SS, Detroit Tigers

The Detroit Tigers are going to have Kevin McGonigle start with the big league team on Opening Day. Considered to be the No. 2 prospect in MLB, the excitement surrounding the 21-year-old is palpable.

Batting lefty, the Pennsylvania native was the 37th overall pick in 2023 and would sign an above-slot deal with the Tigers before quickly moving up in their minor league system. In 20 spring training games, he had an .888 OPS with two home runs, six RBI and two stolen bases.

2. Kazuma Okamoto, 3B, Toronto Blue Jays

Coming over from Japan, Kazuma Okamoto has professional experience and hopes that translates to MLB. The 29-year-old signed a four-year, $60 million contract and is expected to replace much of the production that Toronto lost when Bo Bichette moved on.

In Japan, Okamoto was a star. A six-time All-Star selection in the NPB, he was the Central League home run leader three times and a Mitsui Golden Glove winner twice. He also played internationally for Team Japan in 2023. There are some concerns about catching up to MLB fastballs, but he has plenty of talent.

3. Connelly Early, SP, Boston Red Sox

The Boston Red Sox break spring training with an incredibly deep starting rotation. So, many expected Connelly Early to open in Triple-A, even though he had started a playoff game in 2025. Instead, he earned a job in the rotation as the Red Sox's No. 3 starter.

A former fifth-round pick who played his college ball at Virginia, Early began 2025 in Double-A before being promoted to Triple-A and later MLB as a September call-up. That gives him professional experience, despite still being classified as a rookie. In that brief time, he threw 19.1 innings to a 2.33 ERA and 29 strikeouts. He threw 3.2 innings in a losing effort in the postseason.

4. Konnor Griffin, SS, Pittsburgh Pirates

Technically, Konnor Griffin isn't a rookie. He's still just the top-ranked prospect in all of MLB, who the Pittsburgh Pirates are keeping in the minor leagues. Despite that, most people expect him to break out in the majors at some point in 2026.

This spring, Griffin flashed his power at times. That included a two-home run game. However, he also battled inconsistency, with a .171 batting average and a .261 OBP. Find that consistent ability to get on base in the minors, and he'll be a star in Pittsburgh soon enough.

Daniel Morrison

Dan Morrison is a writer originally from Massachusetts, now residing in Florida. He spent four years at On3, working on the National News Desk there. Prior to that, he’s also contributed at Underdog Dynasty.

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