Mariners vs. Phillies Prediction, Odds, Probable Pitchers and Prop Bets for Tuesday, Aug. 19

Iain MacMillan | Aug 19, 2025

Cristopher Sanchez and the Phillies are home favorites against the Mariners on Tuesday night. / Katie Stratman-Imagn Images

The Philadelphia Phillies took down the Miami Marlins in an offensive shootout on Monday night, winning by a final score of 12-7.

The Mariners have now lost three straight games, which isn't helping their chances of taking the AL West lead. They currently sit 1.5 games back from the Houston Astros, but are still three games clear for the final wild card berth in the American League.

Let's take a look at the odds and my best bets for tonight's interleague matchup.

Mariners vs. Phillies Odds, Run Line, and Total

Odds via FanDuel Sportsbook

Run Line

• Mariners +1.5 (-126)
• Phillies -1.5 (+105)

Moneyline

• Mariners +166
• Phillies -198

Total

• Over 8 (-115)
• Under 8 (-105)

Mariners vs. Phillies Probable Pitchers

• Seattle: Bryce Miller, RHP (2-5, 5.73 ERA)
• Philadelphia: Cristopher Sanchez, LHP (11-4, 2.45 ERA)

Mariners vs. Phillies How to Watch

• Date: Tuesday, August 19
• Time: 6:45 p.m. ET
• Venue: Citizens Bank Park
• How to Watch (TV): NBCSP, ROOTNW
• Mariners Record: 68-58
• Phillies Record: 72-53

Mariners vs. Phillies Best MLB Prop Bet

• Cristopher Sanchez OVER 6.5 Strikeouts (+102) via FanDuel

The Mariners have had a big issue striking since the All-Star Break. Since the pause in play last month, the Mariners have struck out on 25.0% of their plate appearances, which is the third-highest rate in the Majors in that time frame. That number increases to 26.6% when facing left-handed pitchers, and tonight they'll face a lefty in Cristopher Sanchez. After striking out 10 times against the Phillies last night, I expect them to have another poor performance in the strikeout department.

Mariners vs. Phillies Prediction and Pick

This has all the makings of a lopsided affair. It's not just striking out that the Mariners have struggled with since the All-Star Break. They also rank 20th in wRC+ and 25th in OPS in that time frame. The Phillies rank sixth and fifth in those two metrics.

Normally, the Mariners' pitching would give them a fighting chance in most games, but Bryce Miller gets the start for them tonight, and he's had an abysmal 2025 campaign. He has a 5.73 ERA on the season and a 9.50 ERA in his last four starts. A start against a lineup as strong as the Phillies' isn't exactly the best time to turn things around.

I'll bet the Phillies to win this one and cover the -1.5 run line.

Pick: Phillies -1.5 (+105) via FanDuel

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