San Diego Padres 2026 Top Prospects Rankings: Miguel Mendez (No. 5)

The San Diego Padres may lack the might they once had in terms of prospect depth, but that doesn’t mean they lack intrigue down on the farm. Having already explored three-quarters of the team’s top 20 prospects – as voted on by our Padres Mission staff – we turn our attention to one whose intrigue might become relevant rather soon.

Check out prior entries in the rankings here:

• No. 6: Jagger Haynes
• No. 7: Humberto Cruz
• No. 8: Ty Harvey
• No. 9: Ryan Wideman
• No. 10: Kale Fountain
• Nos. 11-15
• Nos. 16-20

Miguel Mendez – Pitcher (San Antonio Missions; Double-A)

With so little depth and so few long-term names on the payroll on the mound for the Padres, it might seem there’s little to look forward to. Miguel Mendez might offer a shift in that mindset. 

Mendez was a quick riser in 2025. He began the season in A-ball, and before 2025 ended, he’d crossed into High-A and made a handful of starts at Double-A. The numbers support such a rapid ascent through the system, too. He made just three starts and threw 11 innings with Lake Elsinore. Therein, he allowed five runs on 11 hits but also struck out 18 hitters. That penchant for swings-and-misses earned him a dozen starts at the next level in Fort Wayne. He built on his early success in posting a 1.32 ERA, a 28.6 percent strikeout rate (70 total), and a 9.8 percent walk rate in 61 1/3 innings. 

That earned him another call-up. He wrapped 2025 with San Antonio, though the results were not quite as good. His ERA sat over eight in 22.1 innings (5.91 FIP) and a homer-to-flyball ratio up near 17 percent. All told, Mendez pitched 95 innings (22 starts), posted a 3.22 ERA, and struck out 29.4 percent of the batters he faced. One imagines that his clunky stint in San Antonio will have him ticketed for Double-A again to start the year, but one also doesn’t have to stretch to see the potential for a cup of coffee down the road if his trajectory stays on course.

What To Like:

Mendez doesn’t make this complicated. His stuff is very good. He brings a quality fastball with plenty of movement that he mixes with a slider and a less-used changeup. Baseball America’s scouting report noted the following: 

"Mendez attacks hitters out of a slightly lowered three-quarters slot with no shortage of arm speed and features a fastball, slider and a changeup. Mendez’s heater sits in the mid-to-upper-90s with both run and ride through the zone. It jumps out of his hand and plays especially well in the top half of the strike zone, which is also where it generates the vast majority of its swings and misses. Mendez’s tight mid-to-upper-80s slider regularly generates empty swings. It flashes plus with sharp two-plane tilt, though against right-handed hitters it will sometimes have more length than depth. Mendez used his upper-80s-to-low-90s changeup just 8% of the time, but its results were encouraging. It garnered a 37% miss rate while flashing effective tumble and fade."

Fastball-slider is a devastating combination on its own, especially with the upside of each pitch. If he can harness the changeup to the point where it becomes a viable third pitch, then you’re talking about him in the big-league mix in fairly short order. 

The most important thing for Mendez thus far, though, has been the growth. In his first stint in affiliated ball back in 2022, he walked hitters at a rate up near 29 percent and struck them out at only half that clip. That number remained high in Low-A in both 2023 and 2024, with walk rates reading 13.3 and 14.9, respectively. That it came down so significantly across the various levels in 2025 is certainly encouraging. Though after that brief trip to San Antonio, it’s the one area where continued improvement will need to be demonstrated.

What To Work On: 

The aforementioned command is, obviously, objective No. 1 for Mendez moving forward. There’s more evidence of him struggling with it than him having it to this point in his professional career. If we’re to assume that this is an aberration wrought by a small sample at a new level, then it’s not overly concerning. 

Beyond the obvious, Mendez needs to get that changeup into the game at a higher rate. It’s extraordinarily difficult to stick as a starter at the major-league level without a third pitch. That Mendez only threw it eight percent of the time last year – even amid the success he was experiencing – speaks to the lack of comfort he has with that offering. If he’s able to grasp command of the other two pitches more fully, then 2026 will present him with an opportunity to get that pitch to be a factor in the broader arsenal.

What’s Next:

Double-A seems like the most likely starting point for Mendez this year. If the command demonstrated last year returns, though, he could be on his way to El Paso before long once the new year begins. 

Beyond that, there are a couple of different routes the Padres could take with him. They could give him a full year of seasoning to harness command and develop the change. That could put him in decent position to grab a rotation spot in camp ahead of the 2027 season (assuming such adjustments are fully realized). There will be opportunities for rotation spots in the same way we’re seeing them this year. 

The other possibility is that we end up seeing Mendez pitching in San Diego before year’s end, albeit as a reliever. A two-pitch pitcher is much more viable in relief. Even with the depth the Padres have in the bullpen, there might be nothing stopping them from wanting to see his upside as a one- or two-inning reliever as he gets adapted to the big-league level. Either way, there’s an intensely bright future here that should be featured as part of the depth chart for the top club in some form or fashion before year’s end.