Wrigleyville Prospect Weekly: Hartshorn Goes Deep Twice, Coppola Throws 5 Hitless Innings at High-A
By Reed Kubiak ·
Wrigleyville Prospect Weekly covers the last 7 days of action for the Cubs farm system.
Josiah Hartshorn: 21 HR, 100 RBI Across Two Levels at 19
Josiah Hartshorn (A+, OF, Rank: 5) went 7-for-26 with two homers, a double, three RBI, and six walks over the week, striking out six times. That line traces who he is: the power showed up, the walks piled up, and the contact held against High-A arms. He now has 21 home runs and 100 RBI across 111 games split between Myrtle Beach and South Bend, a combined slash of .285/.403/.520 that has long since passed "encouraging" and arrived somewhere closer to "this is a legitimate prospect." Over the last 30 days at High-A, he slashed .306/.419/.588 with five homers, five doubles, two triples, and 24 RBI across 23 games, drawing walks at a 16.2 percent clip while keeping his strikeout rate at the same level. The power and the patience are feeding off each other.
The scouting projection is a 55 power, 50 hit switch-hitter whose defensive ceiling is probably first base and whose ultimate projection lands at second-division starter. That framing was already being stress-tested by August, and the stress is not coming from the bat. A 19-year-old posting a .403 on-base percentage with 21 homers across two full-season levels, with a 41.2 percent swing rate and 78.3 percent contact rate, is doing something the projection did not budget for. The patient profile that was supposed to be his on-base mechanism is also functioning as a power amplifier: he is hunting pitches he can damage, and when pitchers attack the zone early, the bat speed and leverage are doing real work. The 15.2 percent walk rate on the season is not an accident. Whether there is a Double-A assignment before this season ends or whether the Cubs let him stay at South Bend and build on a 100-RBI season at 19, the second-division ceiling on his report is going to need another look before long. I would take the over on that projection without much hesitation.
Pierce Coppola: Five Hitless Innings, Seven Strikeouts at South Bend
Pierce Coppola (A+, LHP, Rank: 40) turned in the most dominant start of his professional career on the week: five innings, no hits, no runs, two walks, and seven strikeouts on 42-of-73 pitches for strikes, generating 16 whiffs. For a pitcher whose scouting report projects him as a back-end starter or up-down arm and whose walk rates have been a consistent concern, a hitless outing with a 31.9 percent whiff rate sharpens the conversation. Over the last 30 days at High-A, the ERA sits at 2.12 across 17 innings, with a 0.94 WHIP, six walks, and 17 strikeouts, and the season ERA at South Bend is 3.21 across 28 innings. The combined season line across A-ball and High-A reads 68 innings, 82 strikeouts, and a 3.44 ERA.
He is a big left-hander, 93-to-96 on the fastball with a splitter that can miss bats when the arm speed stays consistent, and the extreme height creates a sight-line problem for hitters that makes average stuff play up. The command has been the honest concern: a 12.5 percent walk rate on the season still reflects the mechanical inconsistency that comes with a long delivery and a frame that takes time to repeat. But the last-30-day walk rate of 8.6 percent against batters faced is a meaningful improvement, and the hitless outing showed what the profile can look like when the fastball stays north-to-south and the splitter finishes at the knees. His injury history and below-average command keep the floor near a long reliever or swingman role, but if the command tightening is real and not just a four-start sample, a path toward the back of a rotation stays open. The most encouraging part of the week was not the no-hit line. It was the 16 whiffs on 73 pitches, suggesting that when he repeats his release point, the stuff is already good enough to overpower High-A bats.
Quick Hits
- Kane Kepley (AA, OF, Rank: 9) · drew eight walks and added a homer over 23 plate appearances at Knoxville, also getting hit twice for a combined 10 times on base, while striking out just four times. The week fits his season profile: a 22.9 percent walk rate and a 12.9 percent strikeout rate at Double-A, with a .500 on-base percentage across 70 plate appearances at the level. His 29.3 percent swing rate over the last 30 days is one of the most selective marks in the system, and the contact rate of 86.9 percent over that same stretch shows it is not passivity but genuine pitch recognition. He has 61 stolen bases on the season across both levels.
- BJ Murray Jr. (AAA, 3B, Rank: 41) · had a strong week, going 8-for-24 with two doubles, a triple, five RBI, and two walks. The .298/.402/.495 season line across 113 Triple-A games is the best sustained offensive stretch of his career, a significant step forward from the .242/.363/.418 he posted in 125 Double-A games last year. The profile is an up-down corner bat, and this year's output at Iowa has made that path look more realistic than it did in April.
- James Triantos (AAA, 2B, Rank: 14) · went 4-for-25 with two doubles, a homer, four walks, and two HBP for seven times on base in the week. The 55 hit tool and contact-first profile are the engine; he is at 84.4 percent contact rate and a 12.1 percent strikeout rate on the combined season. His .301 average at Triple-A across 93 games is a meaningful improvement over the .258 he posted in 102 AAA games last year, and the 22 stolen bases show the 55 speed grade is translating.
- Eduarniel Núñez (AAA, RHP, Rank: 21) · threw 3.1 innings of one-run ball with four strikeouts and two walks in his week's outing. The 96-to-98 mph fastball gives him a weapon that can get Triple-A hitters out when he locates it, but the season ERA across Iowa sits at 3.45 through 15.2 innings with a 18.6 percent walk rate. His control has been the defining limitation across every stop this year, and at 27, the window for meaningful improvement is shorter than the velocity would suggest.
- Nazier Mulé (A+, RHP, Rank: 27) · went 5.1 innings, four hits, one run, two walks, and six strikeouts at South Bend. The 40.7 percent whiff rate over the last 30 days is the most notable number attached to his name right now; the 95-to-98 mph fastball is generating real swing-and-miss even when the command wanders. The ERA over that same stretch is 6.23 across 17.1 innings, which reflects the home runs and walks that follow when the command grade (40) shows up. The strikeout stuff is real. The command question is the only thing standing between him and a more interesting profile.
- Grant Kipp (AAA, RHP, Rank: 11) · struck out seven over three scoreless innings at Iowa, allowing two hits and one walk. The curveball that grades as his best pitch is capable of this kind of outing when he stays on line, but the season ERA at Triple-A is 5.85 across 32.1 innings, and the ERA over the last 30 days is 6.23 with a 17.5 percent walk rate against batters faced. The three-inning scoreless line was a reminder of his ceiling; the surrounding numbers are a reminder of his floor.
- Jostin Florentino (A+, RHP, Rank: 31) · allowed three earned runs on five hits over four innings with six strikeouts and one walk. The ERA at South Bend is 4.53 across 59.2 innings, and over the last 30 days he has pitched to a 3.86 ERA with a 10.0 percent walk rate against batters faced. The step back from his dominant 2025 showing (2.43 ERA at two A-ball levels) was expected when he moved to High-A; how he closes out the season will inform whether a Double-A assignment is realistic next spring.
- Ethan Conrad (A+, OF, Rank: 3) · was placed on the 7-day injured list on August 25, with no confirmed diagnosis available. He had appeared in just two games at South Bend after his promotion, going 0-for-7 in eight plate appearances at the level, though his earlier work at Myrtle Beach showed genuine progress: a .389 average with a .500 on-base percentage over five games in his final stretch there. The IL placement interrupts what was becoming a positive developmental stretch after his strong August at Single-A.
- Nick Dean (AA, RHP, Rank: 23) · was placed on the 60-day injured list on August 20, ending his season at Knoxville. He posted a 3.66 ERA across 46.2 innings and 52 strikeouts before going down. No diagnosis has been confirmed.
- JP Wheat (A+, RHP, Rank: 38) · was activated from the 7-day injured list on August 25 and had not appeared in a game yet at the time of this writing. His season ERA at South Bend sits at 8.00 across 27 innings, and the 46 walks against 30 strikeouts in that sample is a tough command profile to carry at any level.