This story was excerpted from AJ Cassavell’s Padres Beat newsletter. To read the full newsletter, click here. And subscribe to get it regularly in your inbox.

Jackson Merrill is no longer a top prospect. He's a big leaguer for keeps, having graduated from MLB Pipeline's Top Prospects lists earlier this month. (And, based on his impressive start, he’s probably destined to be a big leaguer for a long, long time.)

Merrill, of course, isn't the only rookie to graduate from those rankings. Over the past couple weeks, the group of rookies who broke camp in the big leagues is no longer considered prospects. As a result, MLB Pipeline made its first in-season update to its Top 100 Prospects list this week.

With Merrill off the board -- and Drew Thorpe dealt to the White Sox in the Dylan Cease trade -- the Padres are down to four Top 100 prospects. But it's a pretty impressive group of four.

Here's a look at the early season progress of each:

Ethan Salas (No. 6 overall)
Development is not linear, the Padres often say. As quickly as Salas progressed a season ago, his start to the 2024 campaign has been a slow one. At High-A Fort Wayne, Salas has posted a .171/.282/.234 slash line. The Padres remain impressed with his day-to-day work and his ability to handle a pitching staff. But Salas is being challenged, presumably more than he's ever been challenged on a baseball field. The long-term prognosis is still largely the same. (Salas moved up from No. 7 to No. 6 overall on MLB Pipeline's Top 100 list.) But clearly there's still plenty of development ahead of Salas, and predictions of his possible big league debut as an 18-year-old may have been premature.

Robby Snelling (No. 27)
Snelling jumped five spots in the latest prospect re-rank. Through six starts at Double-A San Antonio, he's posted a 3.86 ERA. It's not quite the dominance he displayed during his rookie season, but Snelling has still transitioned well as a 20-year old in the upper levels of the Minor Leagues. Snelling has plenty of work to do. But there remains a chance he could pitch his way into a late-season callup.

Dylan Lesko (No. 72)
Lesko remains among MLB Pipeline's Top 100 prospects, but his stock has fallen as much as anyone within that list (from 49 to 72). That's a product of Lesko's slow start to the season. He has allowed 19 runs across 19 innings (9.00 ERA), and his command has been erratic at best. He's already walked 23 batters. The Padres are still bullish on the upside. Lesko underwent Tommy John surgery in high school prior to his selection in the first round of the 2022 Draft, and he entered the year having thrown only 33 professional innings. More than anything, they just wanted to see Lesko healthy and on the mound. Now, he is. And he's got some challenges to work through.

Leodalis De Vries (No. 82)
De Vries has played eight games at Single-A Lake Elsinore, and he's posted a .194/.324/.290 slash line. It comes on the heels of what those in attendance described as a dominant showing in extended spring camp. De Vries, the top international prospect in this year's class, earned his way to Single-A quickly with his performance in Peoria. Now he's enduring a bit of a grind -- not unexpected for a 17-year-old playing professional baseball for the first time.

Here's a look around the rest of the system:

Triple-A El Paso: The biggest development in El Paso is the recent promotion of Adam Mazur, the team's No. 5 prospect. Mazur is off to as impressive a start as any pitcher in the system. He posted a 1.95 ERA across six starts with Double-A San Antonio, before pitching six innings of two-run ball in his Triple-A debut on Tuesday.

Double-A San Antonio: Mazur wasn't the only standout on the Missions' pitching staff this season. Snelling and Austin Krob (No. 9) have been sharp. Ryan Bergert (No. 7), meanwhile, has posted a 6.55 ERA but has 25 strikeouts to just five walks in 22 innings. In the bullpen, No. 29 prospect Jayvien Sandridge (2.92 ERA, 21 strikeouts in 12 1/3 innings) is emerging as a candidate for a callup later this season.

High-A Fort Wayne: Playing his first full professional season, Homer Bush Jr. is hitting .269 with a .363 on-base percentage, and he's already swiped 16 bases. The Padres' No. 8 prospect, Bush is making the most of his chance to play regularly.

Single-A Lake Elsinore: No. 27 prospect Jay Beshears, a 2023 sixth-round pick out of Duke, posted a remarkable .320/.489/.454 slash line in 28 games at Lake Elsinore, enough to earn him a callup to Fort Wayne. On the mound, No. 19 prospect Isaiah Lowe has impressed with a 3.24 ERA across six outings (four starts).