The Seattle Mariners host the Arizona Diamondbacks on May 31, 2026. First pitch from T-Mobile Park is scheduled for 4:10 p.m. ET. The game will be broadcast on ARID.
The Mariners are favored by -152 on the moneyline and by -1.5 on the run line. The Diamondbacks are +128 on the moneyline and +1.5 on the run line. The total is set at 7.5 runs.
Find my MLB picks and Diamondbacks vs Mariners prediction below, as well as probable pitchers, weather report, and more.
Diamondbacks vs Mariners Prediction
Diamondbacks vs Mariners Picks:
- Mariners ML / Ketel Marte Over 1.5 Total Bases (+252)
- Ketel Marte Home Run (+340)
Diamondbacks vs Mariners Odds
| Diamondbacks Odds | ||
|---|---|---|
| Spread | Total | Moneyline |
+1.5 -172 | 7.5 -106o / -114u | +128 |
| Mariners Odds | ||
|---|---|---|
| Spread | Total | Moneyline |
-1.5 +142 | 7.5 -106o / -114u | -152 |
Diamondbacks vs Mariners Probable Pitchers
| Merrill Kelly (RHP, ARI) | Stat | Bryce Miller (RHP, SEA) |
|---|---|---|
| 5-3 | W-L | 1-0 |
| -0.1 | fWAR (FanGraphs) | 0.3 |
| 5.25 / 7.19 | ERA / xERA | 2.25 / 2.15 |
| 5.19 / 5.05 | FIP / xFIP | 3.31 / 3.19 |
| 5.3% | K-BB% | 19.4% |
| 32.9% | GB% | 44.4% |
| .270 | BABIP | .273 |
| 88 | Stuff+ | 113 |
| 102 | Location+ | 113 |
Diamondbacks vs Mariners MLB Betting Preview
Bryce Miller looks great! He’s reverted back to his elite 2024 form across his first three outings this season — he started the year on the IL with a left oblique strain, but he sure looks healthy now. He’s running a 2.25 ERA and 1.00 WHIP after 16 frames.
That said, he’s going to have a tough time against Arizona’s formidable lineup spearheaded by Ketel Marte. Marte has been on fire, slashing a .926 OPS over the past month behind four home runs.
Luckily for the M’s, Merrill Kelly has looked lost on the mound, running a 5.25 ERA after eight starts. Seattle has a very versatile lineup, and Kelly likely struggles to shut it down.
I expect the Mariners to have the edge at their home ballpark in Seattle, especially behind a considerable starting pitching advantage.
Diamondbacks vs Mariners Pick, Betting Analysis
I favor Seattle to win this game, but I wouldn’t be surprised if Marte continues to tear it up.
Miller has good control and command of his four-seam fastball, which he prefers to elevate. However, that pitch can be vulnerable against left-handed power hitters, and Marte is one of the league’s best (who also happens to be slugging .626 against fastballs this season).
Like many other hitters in Arizona’s lineup, Marte is super patient in the box. If Miller gets behind in the count against Marte, a four-seam fastball might just be left middle-up in the zone, which should allow Marte a prime opportunity to barrel one up.
Picks:
- Mariners ML / Ketel Marte Over 1.5 Total Bases (+252)
- Ketel Marte Home Run (+340)
