This article was contributed by BetMGM. For more sports betting insights, check out BetMGM.com.

In flipping their record from one game under .500 to nine games over .500 over a 14-day stretch that included 11 wins in 12 games from May 9-22, the Astros allowed a first-inning run one only once: three runs to the Cubs in an eventual 7-6 win on May 17.

That stretch pushed the Astros’ opponent NRFI (no run first inning) rate to the best in MLB at 83%. After allowing two first-inning runs in Wednesday’s loss to the Brewers, they still led all teams at 81.6%.

NRFI odds and YRFI odds (yes run first inning) have exploded in popularity in recent years and are now the fourth-most-popular type of MLB bet at BetMGM, behind only run lines, moneylines and over/under totals. And the Astros, largely thanks to one of the best first-inning pitching staffs in baseball, have become a highly profitable NRFI bet.

As of May 25, only the Marlins (64%) and Blue Jays (58%) had a higher NRFI percentage than the Astros (57%).

Five of the seven Houston pitchers to start a game this season entered Tuesday with a first-inning ERA of 3.60 or lower, including one of the MLB’s best first-inning pitchers, Cristian Javier.

In 11 innings over 11 starts, Javier has allowed two runs on four hits and three walks. His 0.636 WHIP in the first inning is tied for the sixth best in the Majors (minimum 10 starts). Ahead of him on that list is teammate Framber Valdez, who is one of two pitchers with zero walks, zero wild pitches and two or fewer runs allowed in the first inning -- the other is Zac Gallen of the D-backs.

For context: The co-favorites in BetMGM’s AL Cy Young betting, Gerrit Cole and Shane McClanahan, have allowed 16 combined hits and 12 combined walks. And they both have a WHIP over 1.10.

While the Astros’ surge in first-inning offense over that 12-game stretch from May 9-22 -- 12 total first-inning runs across six different games -- complicated issues for NRFI bettors, the pitching staff is ensuring its opponent NRFI and overall NRFI rates remain among the best in baseball.

You can view NRFI odds and more betting opportunities for all Astros games at the BetMGM online sportsbook.