Best MLB prop bet for today, 10/7: Tough matchup for Merrill Kelly

All 4 wild-card series resulted in 2-0 sweeps this season, leaving us without MLB action both yesterday and today. With the divisional round starting up tomorrow the betting markets are open and moving and there is a play I am aiming to lock in early. Our first 2 playoff prop bets came in games involving the Philadelphia Phillies, but we will shift focus this time around and head to Los Angeles for the Dodgers Game 1 matchup with the Arizona Diamondbacks.

Let’s dive in!

Merrill Kelly, ARI, Under 5.5 strikeouts (-135)

Odds available at BetMGM, DraftKings and Caesars sportsbooks at time of publishing. Playable to -155 odds.

The Arizona Diamondbacks were part of a very tight NL wild-card race this season, clinching their positioning in the final week. This resulted in using their top 2 arms, Zac Gallen and Merrill Kelly, in their 2nd and 3rd to last Games of the regular season. With the quick turnaround to postseason play, rookie right-hander Brandon Pfaadt was tasked with the Game 1 start against Milwaukee. Arizona won both Games of that abbreviated series in Milwaukee despite this, and now benefit from being able to use Kelly and Gallen in 4 of the 5 Games this series if it lasts that long. The issue with Arizona’s chances in this series, however, is that their top 2 arms are not in the greatest of form and both guys have failed in matchups with the Dodgers this season. I will save my full Gallen analysis for Game 2, but let’s dive in on the matchup at hand for Kelly.

The 34-year-old right-hander made 30 regular-season starts in 2023, eclipsing this 5.5 strikeout prop in 16 of those outings. Against the Dodgers, however, his success in that department and in general saw a significant dip. Kelly made 4 starts against Los Angeles this season, totaling 4, 4, 2 and 1 strikeout in those games. His combined 20.1 innings of work in those 4 starts resulted in 13 walks to 11 strikeouts, while also surrendering 27 hits. He was fortunate to escape with a 3.98 ERA across that sample of work but is unlikely to skate past once again if allowing that many baserunners.

His struggles against this organization are not limited to this season’s matchups, either. Across a combined 269 PA vs Kelly from active Dodgers, they have produced a .318 AVG and .882 OPS. Mookie Betts, Freddie Freeman, Max Muncy, Will Smith and Chris Taylor all have sample sizes of over 30 PA against Kelly, and their familiarity with his arsenal and approach should help significantly.

Another concern with Kelly this season has been his performance when away from his home ballpark. The #2 starter for Arizona held opponents to a .183 AVG while recording a 10.19 K/9 and 2.59 ERA across 93.2 home innings but saw his numbers drop across the board when on the road. In those 84 innings Kelly allowed a .261 AVG, 4.07 ERA and saw his K/9 fall to below 1 per inning at 8.68 or 22.7%. At the end of August he made a start in Los Angeles, allowing 12 hits, 3 walks and 7 earned runs with only 1 strikeout recorded across 87 pitches and 5 full innings. With this being the postseason now, there is no such thing as saving the bullpen for the long haul, and with the series taking a break after Game 1 Arizona should have no hesitation heading to the bullpen if Kelly shows any early signs of struggles.

Even if Kelly does perform well in this Game, strikeouts haven’t been part of his success in recent outings. His final 3 regular-season starts against the Giants, Yankees and Astros saw 18.2 innings with only 4 earned runs allowed, but Kelly stayed under this total with 5 strikeouts in each of those outings. He registered a single-digit swinging strike rate in 3 of his 4 starts against the Dodgers this season which makes sense given they had the 9th lowest swinging strike rate as a team since the all-star break. Overall, against right-handed pitching in that sample the Dodgers recorded the 6th-lowest strikeout rate while producing the 2nd-highest wOBA and a 123 wRC+. They are also a patient group which should help run up the pitch count of Kelly and lead to a shorter than usual outing. I lean toward his under 17.5 outs recorded prop, as well, but prefer the strikeout angle because I believe he can stay under this 5.5 mark even if completing 6 full frames.