Pittsburgh’s 2026 improvement was not built solely at PNC Park. The farm system supplied real help to the Major League roster, from Konnor Griffin taking over at shortstop to Bubba Chandler making 30 starts, and the next wave has continued moving through the organization with a few less-publicized names pushing for a louder place on the board.
| Player | Level/Role | 2026 Line |
|---|---|---|
| Reinold Navarro, LHP | Two levels | 2.96 ERA, 24 appearances, 17 starts, 15.38 K/9 |
| Connor Wietgrefe, LHP | Double-A/Triple-A | 3.27 ERA |
| Rafael Sterling, RHP | Age-19 season | .211 opponents’ average, 108 2/3 innings |
| Jhonny Plaz, OF | High-A Greensboro | .305 average, 18 HR, 94 games |
| Tejera, OF | Florida Complex League | .296 average, .960 OPS, 7 BB in 9 games |
Navarro gives the left side of the system another arm
Reinold Navarro, Pittsburgh’s No. 21 prospect, spent his age-19 season showing why he has become one of the more interesting left-handers in the pipeline. Across 24 outings, including 17 starts, he posted a 2.96 ERA at two stops and struck out hitters at a 15.38-per-nine-inning clip.
Only Hunter Barco, ranked No. 16 in the system, sits ahead of Navarro among the club’s left-handed pitching prospects. Navarro’s fastball has plus life and his slider has been a put-away pitch, a combination that played especially well at Single-A Bradenton.
His late-August move to High-A Greensboro came with the usual warning label. In a park that tends to favor hitters, Navarro allowed a 5.59 ERA over 9 2/3 innings. The rough first look at that level did not erase what he had already established earlier in the year.
A teenage outfielder is making his signing bonus look small
Tejera turned 18 in July and remains years from the big leagues, but he made a quick first impression after reaching the Rookie-level Florida Complex League. The left-handed hitter batted .296, carried a .960 OPS and drew seven walks in nine games.
The Dominican Republic signing received a $95,000 bonus, the 12th-largest in Pittsburgh’s international class. He has since entered the organization’s Top 30 following Esmerlyn Valdez’s graduation in July. At 6-foot-2, Tejera still has room to add strength, but the early offensive work has already brought him onto the radar.
Wietgrefe keeps earning his way upward
Connor Wietgrefe was a seventh-round selection from Minnesota in the 2024 Draft, and the 24-year-old has spent three pro seasons making the understated case for himself. Over 277 1/3 career innings, the left-hander owns a 3.12 ERA.
He followed that work with a 3.27 ERA between Altoona and Indianapolis in 2026, putting a 40-man roster decision in view. Wietgrefe generally works around 91 mph rather than overwhelming hitters with velocity, but he has repeatedly demonstrated the ability to navigate a lineup and get outs.
Sterling finished with a better command line
Rafael Sterling’s overall ERA through his first two professional seasons sits at 4.92, but the right-hander took a meaningful step forward in his age-19 campaign. His walk rate fell from 6.09 per nine innings in 2025 to 3.73 in 2026, while opposing hitters managed just a .211 average over 108 2/3 innings.
That progress earned Sterling a High-A Greensboro promotion before his 20th birthday. In his final appearance of the season on Sept. 2, he struck out nine over five innings, walked one and surrendered two solo homers. It was a useful closing snapshot of both the upside and the work still in front of him.
Plaz has climbed into the system’s first tier
Jhonny Plaz did not merely make incremental progress. He began the season ranked No. 22 among Pittsburgh prospects and finished it at No. 7 after hitting .305 with 18 home runs in 94 High-A games.
The 21-year-old outfielder brings power to the plate and a strong throwing arm in the field. A move early in 2027 would provide a sharper test of whether the Greensboro breakout can travel. Pittsburgh will also need to add Plaz to its 40-man roster to keep him out of the Rule 5 Draft.
Hernandez’s timetable remains the big question
Seth Hernandez, regarded as baseball’s leading right-handed pitching prospect, entered the summer with an ambitious target. In early July, he said he hoped to reach the Major Leagues before turning 21 on June 28, 2027.
A left oblique injury later that month ended his season and kept him at High-A Greensboro rather than sending him on to Double-A Altoona. The 2027 debut remains possible, but Hernandez will have to recover lost development time and continue pitching at a level that forces Pittsburgh’s hand.
For now, the organization has no shortage of recognizable names at the top, including Hernandez, Edward Florentino, Murf Gray, Wyatt Sanford and Easton Carmichael. But Navarro, Tejera, Wietgrefe, Sterling and Plaz gave the system a different kind of depth in 2026: players who turned quieter assignments into reasons to keep watching.
