The Seattle Mariners (29-23) host the Washington Nationals (24-29) on Tuesday, May 27, 2025. First pitch from T-Mobile Park is scheduled for 9:40 p.m. ET; the game will be broadcast on MLB Network.
Continue reading to find my Nationals vs Mariners prediction and MLB betting preview for Tuesday's night game.
Washington Nationals vs Seattle Mariners Prediction, Pick
- Nationals vs Mariners pick: Over 8
My Nationals vs Mariners best bet is on the over. Make sure to find the best odds by checking our live MLB odds page.
Nationals vs Mariners Odds
| Nationals Odds | ||
|---|---|---|
| Spread | Total | Moneyline |
+1.5 -155 | 8.5 -105o / -115u | +140 |
| Mariners Odds | ||
|---|---|---|
| Spread | Total | Moneyline |
-1.5 +130 | 8.5 -105o / -115u | -165 |
Nationals vs Mariners Projected Starting Pitchers
| Mitchell Parker (WAS) | Stat | Logan Evans (SEA) |
|---|---|---|
| 4-3 | W-L | 2-1 |
| 1.1 | fWAR (FanGraphs) | 0.0 |
| 4.39 / 3.85 | ERA /xERA | 3.33 / 4.87 |
| 3.76 / 5.12 | FIP / xFIP | 4.92 / 4.15 |
| 1.30 | WHIP | 1.44 |
| 4.6 | K-BB% | 10.3 |
| 43 | GB% | 37.2 |
| 92 | Stuff+ | 99 |
| 102 | Location+ | 99 |
Nationals vs Mariners Preview, Prediction
Nationals Betting Preview: Can't Trust Parker
The Nationals have been a scrappy team thus far in 2025, but their results haven't met their expectations.
They've won three of their last five entering Tuesday's game, but I see trouble brewing with Mitchell Parker on the mound.
Parker has 55 innings pitched but only 36 strikeouts thus far, suggesting he's allowing a lot of contact. Opposing hitters have a 45% hard-hit rate, which means Parker is prone to getting into trouble.
The Mariners are also a slightly stronger offensive unit against southpaws, and I have a lot of concerns for Parker moving forward.
He also has an 11% walk rate, which is dangerous considering the amount of contact he allows to begin with.
With Parker on the mound, there's no way I can feel comfortable backing the Nats, but their offense has a decent matchup.
Against right-handers, they're a far better offensive unit, which is no surprise given the loaded talent they have coming from the left side of the plate.
James Wood, CJ Abrams and Luis Garcia all have xSLG's above 455 against right-handers, so it won't be surprising to see the Nats' offense score some runs.
Who knows if that'll be enough with Parker on the mound.
Mariners Betting Preview: Plenty of Question Marks
The Mariners draw a great matchup on Tuesday against Parker, but that's not compelling enough for me with Logan Evans on the mound. Evans enters Tuesday's game with a 3.33 ERA in 27 innings pitched, but the underlying metrics thus far suggest he's been fortunate.
Evans currently has an 18% strikeout rate and a 19% whiff rate, both of which are well below the league average. His xERA is 4.87, which is 1.5 higher than his current ERA.
Evans doesn't walk many hitters and limits hard contact fairly well, but opponents have a xBA of .299 and only sport a 37% ground-ball rate. Those aren't compelling metrics whatsoever, and the Nats' offense is an underrated group.
Offensively, the Mariners should have success against Parker all night long, and the backend of the Nats' bullpen has also been shaky for most of the season.
Plenty of offense should come from the Mariners on Tuesday, but I have too many questions about Evans' performance. That means the Mariners don't warrant a wager.
Nationals vs Mariners Prediction, Betting Analysis
Tuesday is a great spot to take an over. Seattle's offense has struggled a bit lately, but it's still 10th in the majors in runs scored per game. There's plenty to like about the matchup against Parker.
For the Nationals' offense, I also think they'll do damage against Evans, which will help us surpass the total. They're a stronger offensive team against right-handers, and Evans' inability to miss bats is a primary concern.
Both offenses should thrive in Seattle.
Pick: Over 8
Moneyline
I don't have a play on the moneyline.
Run Line (Spread)
I don't have a play on the run line.
Over/Under
Based on the starting pitchers in this matchup, I'm taking the over.
