PEORIA, Ariz. — The No.5 starter.
It seems so straightforward.
It is not.
The designation itself is so nebulous as to not be an actual thing.
“Hopefully we get into a spot where you don’t know the difference between your five and your three, your three and your one, your two and your four,” Padres pitching coach Ruben Niebla said. “You’re just deploying a good pitcher out there.”
German Marquez #33 of the San Diego Padres participates in drills during spring training workouts at the Peoria Sports Complex on Monday, Feb. 16, 2026 in Peoria, Ariz.(Meg McLaughlin / The San Diego Union-Tribune)
Five pitchers are currently vying for what is likely one spot at the back end of the Padres’ rotation.
As some voices in the organization argue whether the in-house candidates are good enough to round out a rotation that will help lift them into the postseason, it seems like a good time to consider just what it is the Padres will be asking of Walker Buehler or Germán Márquez or Triston McKenzie or Marco Gonzales or JP Sears.
Or what they will be asking of some combination of them that will at some point also include Griffin Canning, who would likely have the job in hand if he were not working back from an Achilles injury that will almost certainly sideline him at least for the bulk of April and possibly longer.
And/or what they will be asking of all of the above plus Matt Waldron and/or Jackson Wolf and/or Miguel Mendez and/or some surprise contributor who has yet to be signed or could rise through the minors quicker than expected or be acquired in a trade.
The muddled reality of what is so succinctly stated as the battle for the fifth spot in the rotation is that spot will almost certainly end up being filled by several people.
Kyle Hart began last season as the Padres’ No.5 starter and lasted five starts before being sent to Triple-A. Stephen Kolek took over the fifth slot in the rotation. When starter Michael King went down with a nerve issue near his shoulder, Hart came back for one start in the fifth spot before Ryan Bergert settled in there. He missed one start after being hit on the forearm by a line drive, and Waldron filled in. Bergert returned and remained until he and Kolek were traded at the deadline. Nestor Cortes and Sears, both acquired at the trade deadline, made starts in the fifth spot.
It almost always takes a village. In all, the Padres had 10 pitchers make at least five starts and 14 pitchers start at least one game last season.
No team in 2025 had fewer than six pitchers make at least five starts, and 23 teams had eight or more make at least five starts. Half of the league’s 30 teams had at least 14 pitchers make at least one start.
Many teams’ projected “fifth starter” ended up having their second- or third-best ERA. Some “fifth starters” made the most starts of anyone in the rotation.
San Diego Padres starting pitcher Matt Waldron pitches against the Atlanta Braves during the first inning at Petco Park on Friday, July 12, 2024 in San Diego, CA. (Meg McLaughlin / The San Diego Union-Tribune)
It was just two seasons ago that Waldron, the team’s fifth starter, posted a 2.76 ERA over 14 starts in the middle of the season. In the 2½ months that stretch comprised, the rest of the team’s starters combined for a 4.35 ERA. Only Michael King’s 3.00 ERA came close to Waldron’s excellence in that time.
“If you’re expecting to be a playoff-contending team — and there are tiers to being that playoff-contending team — your fifth starter has to be a guy that you can depend on,” Niebla said. “If your expectations are like, ‘Hey, we’re probably not (a playoff team),’ then let’s develop guys into that role. Let’s get our minor-league system guys into that role and see what we have. We believe we’re a top-four playoff team. So our fifth starter, we are expecting that guy to be able to get us some wins. It’s guys that are gonna keep us in games and give us innings when we need to. Our one through three, the expectation is seven (innings). But there are gonna be three-(inning outings). So our five has got to be able to do seven (innings) sometimes.”
That is the ideal.
What can be said with some level of certainty regarding a contending team is that it is imperative to have as many pitchers as possible capable of covering at least five innings while limiting damage.
If the Padres’ bullpen is as dependable as they expect, that could be a winning formula that pushes them from being the 79 wins FanGraphs projects them to have (based largely on concerns about rotation depth) to a third consecutive season with at least 90 victories.
The Padres were 63-24 last season when their starting pitcher went at least five innings and allowed three or fewer runs. That was significantly better than the .588 average winning percentage across MLB in such games.
The five Padres pitchers who worked in the fifth spot last season combined for 16 starts of five or more innings with three or fewer runs allowed. The Padres were 11-6 (.647) in those games.
Peoria, AZ – February 22: Triston McKenzie #25 of the San Diego Padres walks in the dugout after being pulled against the Los Angeles Dodgers during a spring training game on February 22, 2026 in Peoria, AZ. (K.C. Alfred / The San Diego Union-Tribune)
While it is difficult to determine an apples-to-apples comparison of teams’ No. 5 starters, given injuries in spring training, the different makeup of staffs and other factors, the pitcher who began as the No.5 starter for the other 11 playoff teams in 2025 averaged 21 starts, 109⅓ innings and a 4.62 ERA.
There is no pretending the Padres are looking for an ace among those competing to join Nick Pivetta, Michael King, Joe Musgrove and Randy Vásquez in this season’s rotation. But neither do they concede they are looking for anything less.
“He’s the ace on the day he’s pitching,” manager Craig Stammen said of the fifth starter. “That’s the No. 1 mentality for that guy. You don’t want to ever limit anybody when they take a big-league mound. You want them to feel like they’re our best option, and that guy is on that day. We know the fifth starter is probably not as talented as the ace, but we’re expecting to win that day, and that’s why we’re putting him out there.”