San Diego Padres vs. San Francisco Giants Prediction – September 13, 2026
As the 2026 MLB season enters its final weeks, every game carries postseason implications. On September 13, the San Diego Padres travel north to face the San Francisco Giants, and the WP Baseball Predictor model is Confident in the Padres moneyline, listing San Diego as a strong favourite. Here's a full breakdown of why the model leans heavily toward San Diego in this late-season NL West showdown.
Starting Pitcher Matchup: Pivetta vs. Webb
The headline story of this matchup is a dramatic pitching disparity, and it may be the single biggest reason WP's model is so decisive in its pick.
Nick Pivetta (San Diego Padres)
Nick Pivetta takes the mound for San Diego carrying one of the most eye-catching numbers you'll find anywhere in baseball right now: an xFIP of 1.55. Expected Fielding Independent Pitching strips away defense and luck to measure a pitcher's true underlying performance, and a mark of 1.55 is historically elite. Pivetta has clearly been pitching at an extraordinary level, limiting hard contact and suppressing run expectancy in a way that makes him one of the most dangerous starters in the game at this stage of the season.
Logan Webb (San Francisco Giants)
Logan Webb is no slouch — he has been one of the Giants' most reliable arms for years — but his current xFIP of 3.52 represents a significant step down from what Pivetta is producing. While a 3.52 xFIP is a perfectly respectable figure for a mid-rotation starter, placed head-to-head against Pivetta's 1.55, the gap is stark. San Diego's offense figures to have a meaningful advantage in run-scoring opportunity when you consider how starkly these two underlying metrics diverge.
Team Stats: A Closer Look at Both Rosters
Beyond the pitching matchup, the broader team metrics tell a competitive but telling story:
- Padres wOBA: 0.308 | Giants wOBA: 0.309 — The offenses are virtually identical in overall production, making the pitching matchup the true differentiator.
- Padres FIP: 4.24 | Giants FIP: 4.30 — San Diego's pitching staff holds a slight edge in fielding-independent performance.
- Padres ERA: 3.91 | Giants ERA: 4.37 — San Diego's rotation and bullpen have been meaningfully better at preventing runs over the course of the season.
With the offenses essentially even, San Diego's superior pitching staff — led tonight by an elite Pivetta — gives them a clear structural advantage.
Injury Report: Key Absences for Both Clubs
Injuries are always a factor in late-season baseball, and both rosters are dealing with some notable absences heading into Sunday.
Padres Injuries
- Miguel Andujar – Wrist (10-Day IL)
- Humberto Cruz – Elbow (Out)
- Yu Darvish – Elbow (Out)
- Jeremiah Estrada – Shoulder (15-Day IL)
- Gavin Sheets – Foot (10-Day IL)
The loss of Yu Darvish is a significant long-term blow to the rotation, though it has no direct impact on today's start with Pivetta on the mound. Bullpen depth could be a concern if Pivetta is pulled early, as Estrada's absence thins out San Diego's relief options.
Giants Injuries
- Willy Adames – Elbow (10-Day IL)
- Victor Bericoto – Knee (10-Day IL)
- JT Brubaker – Ribs (15-Day IL)
- Sam Hentges – Forearm (15-Day IL)
- Luis Hernandez – Hip (7-Day IL)
San Francisco's injury situation looks notably problematic. Willy Adames' absence removes a key offensive contributor from the lineup, and the loss of multiple relievers — Hentges and Brubaker — puts real pressure on a bullpen that may need to support Webb should he exit early.
Dark Horse Home Run Picks
🔴 Padres Pick: Jackson Merrill
Keep an eye on Jackson Merrill to go deep against Logan Webb. Merrill has the power profile to exploit any mistake over the plate, and with Webb's xFIP sitting at 3.52, there is genuine opportunity for a long ball in this matchup.
🟠 Giants Pick: Bryce Eldridge
For the Giants, Bryce Eldridge is the dark horse candidate to provide a surprise home run moment against Pivetta. Even elite pitchers surrender the occasional mistake, and Eldridge has the raw power to make them pay on the right pitch.
WP Baseball Predictor Final Pick
The WP Baseball Predictor is Confident on the San Diego Padres moneyline as a strong favourite on September 13. The dominant xFIP advantage held by Nick Pivetta over Logan Webb, combined with San Diego's superior team pitching metrics and San Francisco's mounting injury concerns — particularly in the lineup and bullpen — all point toward a Padres victory. This is one of the more compelling model-backed plays of the final month of the regular season.