3 Best MLB NRFI Bets on Monday 8/18/25

The MLB season is an annual marathon that gives us months of daily betting markets to consider.

While traditional player props like home runs and strikeouts remain popular options, one market that's gained steam is betting whether or not no runs will be scored in the first inning -- aka a No Run First Inning (NRFI) bet.

On FanDuel Sportsbook's MLB odds, we can find NRFI odds listed as 1st Inning Over/Under 0.5 Runs odds under each MLB game.

Where can we find value in this unique prop market today?

Please note: lines and projections are subject to change throughout the day after this article is published.

NRFI Betting Picks for Today

Seattle Mariners at Philadelphia Phillies

Under 1st Inning 0.5 Runs (-130)

On Monday, we have a fun pitcher matchup on deck in the Seattle Mariners-Philadelphia Phillies showdown, with Logan Gilbert (10-7 NRFI record) taking the mound against Ranger Suarez (17-1 NRFI record). Even though Gilbert has struggled with homers in the opening frame (1.60 HR/9 in the first inning) and won't be on the bump at pitcher-friendly T-Mobile Park, the numbers still point toward him contributing toward a NRFI.

Aside from his issues with giving up dingers, Gilbert possesses the fourth-best xFIP (2.19) and fourth-highest strikeout rate (37.7%) in the first inning among pitchers with 10-plus starts in 2025. Despite the Phillies notably having Kyle Schwarber and Bryce Harper at the top of their order, they've tallied the fifth-highest strikeout rate (26.5%) in the opening inning over the last 30 days, paving the way for Gilbert to generate whiffs en route to recording three quick outs.

Although Suarez carries a 4.16 xFIP in the first inning this season, he's also posting a 25.0% strikeout rate, 0.72 WHIP, .163 BABIP, and 0.0 HR/9 to begin his starts. In addition to the Mariners logging the 12th-worst wRC+ (100) and 4th-highest strikeout rate (28.1%) in the first inning across the last 30 days, they've also notched the 13th-worst wRC+ (95) and 5th-highest strikeout rate (25.5%) versus southpaws during that same span.

Baltimore Orioles at Boston Red Sox

Under 1st Inning 0.5 Runs (-125)

Trevor Rogers (11-0 NRFI record) has now made 11 starts for the Baltimore Orioles this year, and the left-handed hurler has impressed with a 5-2 record, 3.71 SIERA, 3.63 xFIP, and a career-best 5.7% walk rate. As for his performance in the first inning of his outings, Rogers owns the 17th-best xFIP (2.90), 19th-best WHIP (0.91), 20th-best BABIP (.208), and 14th-highest strikeout rate (32.6%) among pitchers with 10-plus starts under their belt.

While the Boston Red Sox have the sixth-lowest NRFI rate (64.1%) at home, they are recording the 14th-worst wRC+ (98) and 12th-worst ISO (.151) against left-handed pitching over the last 30 days. Boston is also registering the highest groundball rate (48.8%) versus lefties in the last 30 days, so Rogers' 58.3% groundball rate in the first inning could come in handy for Monday's contest.

Backing Dustin May (13-7 NRFI record) in the NRFI market certainly comes with plenty of risks, but he's looked solid since joining the Red Sox, and the Orioles have the ninth-highest NRFI rate (75.0%) on the road. Besides May achieving a NRFI in each of his first two starts for Boston, Baltimore has the third-worst wOBA (.278), third-worst wRC+ (76), and seventh-highest strikeout rate (23.9%) in baseball across the last 14 days.

Cleveland Guardians at Arizona Diamondbacks

Over 1st Inning 0.5 Runs (-111)

At the moment, we don't have a confirmed starting pitcher for the Arizona Diamondbacks on Monday, but I want to take a chance in the YRFI market due to the Diamondbacks and Cleveland Guardians having stellar metrics in the first inning recently.

Aside from Gavin Williams (17-7 NRFI record) posting an underwhelming 4.23 xFIP, 12.2% walk rate, and 2.60 HR/9 in the first inning this season, Arizona has logged the second-best wRC+ (182), fourth-best ISO (.297), and fourth-lowest strikeout rate (18.3%) in the opening frame over the last 30 days.

On the season, Williams is also producing a 4.97 xFIP, 1.38 WHIP, 14.0% walk rate, and 1.50 HR/9 on the road (compared to a 3.52 xFIP, 1.25 WHIP, 10.9% walk rate, and 1.06 HR/9 at home). Meanwhile, the Diamondbacks love playing at Chase Field, accruing the highest YRFI rate (43.3%) at home in 2025.

Currently, Zac Gallen (16-9 NRFI record) could potentially start for Arizona on Monday, and he's struggled to the tune of a 4.51 xFIP, 10.0% walk rate, and 1.80 HR/9 in the first inning this year. Even if Gallen isn't named the starter, the Guardians are sporting the fifth-best wRC+ (162), sixth-best ISO (.267), and seventh-lowest strikeout rate (19.4%) in the opening inning across the last 30 days of action.

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The above author is a FanDuel employee and is not eligible to compete in public daily fantasy contests or place sports betting wagers on FanDuel. The advice provided by the author does not necessarily represent the views of FanDuel. Taking the author's advice will not guarantee a successful outcome. You should use your own judgment when participating in daily fantasy contests or placing sports wagers.