The San Diego Padres wrap up their Sunday slate at Petco Park on September 20, 2026, hosting the Miami Marlins in a 4:10 p.m. ET first pitch. Walker Buehler takes the ball for San Diego opposite Miami's Sandy Alcantara in a pitching matchup that, on name value alone, gives this late-regular-season contest genuine intrigue. With September in full swing and roster spots and standings positions still very much in play, the Padres need every win they can squeeze out of their remaining home dates before the calendar closes.
Starting Pitchers: Walker Buehler vs. Sandy Alcantara
Buehler gets the nod for San Diego. The right-hander has had an up-and-down journey back from Tommy John surgery, and every start at this point of the season is an opportunity to build momentum heading into the offseason. The Padres will need him to work deep into the game, limit walks, and keep the ball in the yard — straightforward asks, but ones that define whether he gives the bullpen a genuine rest or burns through it early.
Alcantara is no soft touch on the other side. The Miami right-hander, a former NL Cy Young Award winner, built his reputation on elite stuff and the ability to eat innings. Even in a season where the Marlins have not been a factor in the playoff race, Alcantara brings the kind of arm that can shut a lineup down regardless of standings. The Padres cannot afford to sleep on him simply because Miami is the opponent.
Keys to Watch for San Diego
- Buehler's command: His ability to locate his fastball and deploy his secondary pitches effectively will set the tone. If he is sharp early, the Padres' offense gets time to work.
- Squaring up Alcantara: The Miami starter has historically been one of the toughest pitchers in the NL to barrel up. San Diego's hitters will need patience and disciplined at-bats to get into his pitch count and create opportunities late in the game.
- Petco Park crowd energy: September home games carry weight. The atmosphere at Petco Park can be a genuine factor when the Padres are rolling, and the lineup will feed off it if the team jumps on Alcantara early.
- Bullpen management: Should Buehler exit before the sixth inning, San Diego's relief corps will face meaningful innings against a Marlins lineup that, while not feared, is capable of damage against a taxed pen.
Prediction
This one hinges on which version of Buehler shows up. If he replicates a clean, efficient outing and the Padres show patience against Alcantara — working counts and taking what the right-hander gives them rather than fishing for big swings — San Diego has the home-field edge and the lineup depth to grind out a win. Alcantara will make them earn it, but Petco Park in September with something to play for is a good place to be. Padres win, 3-2.
Catch the game on Padres.TV Presented by UC San Diego Health, or listen on KWFN 97.3 FM and XEMO 860 AM for Spanish-language coverage.
