3 Best MLB NRFI Bets on Friday 8/15/25

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
Philadelphia Phillies at Washington Nationals
Under 1st Inning 0.5 Runs (-132)
Zack Wheeler (19-4 NRFI record) has been one of the best pitchers in baseball this season, registering the second-best SIERA (2.64), third-best WHIP (0.93), and highest strikeout rate (33.5%) among qualified hurlers. The Philadelphia Phillies' ace has also excelled in the first inning, logging the 10th-best xFIP (2.77), 2nd-best WHIP (0.70), and 23rd-best strikeout rate (29.8%) in the opening frame among pitchers with 10-plus starts in 2025.
While Wheeler has given up multiple earned runs in each of his last five outings, he has a 2-0 NRFI record versus the Washington Nationals this season, and he's got the upper hand in nearly every matchup with his 98th percentile xERA (2.44), 97th percentile xBA (.196), and 89th percentile walk rate (5.5%). Across the last 30 days, the Nationals are posting the 14th-worst wRC+ (105), 11th-worst OBP (.304), and 4th-highest strikeout rate (28.4%) in the first inning, so there's confidence in Wheeler getting three outs before giving up a run.
1st Inning Over/Under 0.5 Runs
On the flip side, MacKenzie Gore (16-8 NRFI record) is coming off a bounce-back start where he racked up 10 Ks while shutting out the San Francisco Giants. Along with Gore producing a solid 3.47 xFIP and 25.0% strikeout rate in the opening inning, the Phillies have the eighth-highest NRFI rate (76.2%) on the road this season compared to the third-lowest NRFI rate (60.3%) at home.
Seattle Mariners at New York Mets
Under 1st Inning 0.5 Runs (-113)
Although the Seattle Mariners and New York Mets both have lineups that can generate fireworks to begin games, they've both struggled in the first inning across the last 30 days. Entering Friday's showdown, the Mariners have tallied the 10th-worst wRC+ (95) and 3rd-highest strikeout rate (28.6%) in the opening frame in the last 30 days, while the Mets have the 13th-worst wRC+ (100) and 10th-worst OBP (.297) in the same span.
The pitching matchup also adds some intrigue in the NRFI market, as Luis Castillo (23-3 NRFI record) is set to take on Sean Manaea (4-1 NRFI record). Despite Castillo recording the lowest strikeout rate (20.9%) and lowest swinging strike rate (10.8%) of his career, he's earned the 15th-best SIERA (3.28), 14th-best WHIP (0.95), 4th-lowest walk rate (3.0%), and 25th-highest strikeout rate (24.7%) among pitchers over his last seven starts since July 5.
1st Inning Over/Under 0.5 Runs
Meanwhile, Manaea boasts the fifth-best xFIP (1.82), fourth-best WHIP (0.60), and fifth-highest strikeout rate (38.9%) in the first inning among pitchers with five-plus starts under their belt. Manaea has also yet to surrender a homer or issue a walk in the opening frame this year, giving us enough to place some confidence in him to pitch a clean inning to begin Friday's contest.
Miami Marlins at Boston Red Sox
Over 1st Inning 0.5 Runs (-115)
While the pitching matchup in the Mariners-Mets clash has me interested in a NRFI, the pitchers in Friday's bout between the Miami Marlins and Boston Red Sox is steering me toward taking a YRFI. Currently, Sandy Alcantara (15-8 NRFI record) and Lucas Giolito (12-6 NRFI record) are slated to be on the bump in this contest.
Ahead of his 24th start of the campaign, Alcantara has a 4.42 xFIP and just an 18.2% strikeout rate in the first inning. And along with Boston notching the fifth-lowest NRFI rate (63.9%) at home this season, Alcantara is tallying a woeful 5.24 xFIP, 1.89 WHIP, and 1.54 HR/9 on the road.
1st Inning Over/Under 0.5 Runs
On the season, Giolito has been dismal in the opening inning, accruing a 5.18 xFIP, 1.78 WHIP, 13.6% walk rate, and 3.00 HR/9 to begin his starts. Aside from the Marlins scoring a run in the first inning in each of their last two games, they are sporting the 11th-best wRC+ (141), 11th-best ISO (.220), 7th-best OBP (.358), and 10th-highest walk rate (9.2%) in the opening inning across the last 30 days.
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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.