How and where to bet MLB player prop picks and odds for Aug. 30: Jack Flaherty among best bets

We’re officially near the end of August, which means the 2025 MLB regular season is nearing its conclusion. Saturday, Aug. 30, has another loaded slate with 15 games on the schedule, including Mariners at Guardians, Tigers at Royals, Brewers at Blue Jays and Braves at Phillies. 

The SportsLine Projection Model simulates every MLB game 10,000 times. It entered Week 21 of the 2025 MLB season at a profitable 31-23 on top-rated MLB money line picks. The Inside the Lines team has locked in on its most favorable props for Saturday’s games. Here is their best play.

Best MLB player prop for Saturday, Aug. 30

• Jack Flaherty Over 4.5 strikeouts

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Best MLB prop on Saturday

Jack Flaherty Over 4.5 total strikeouts

Chris Sale is expected to return to Atlanta’s rotation on Saturday, and his Over 6.5 line is posted this morning, which usually means it’s a confirmed start. We have slight betting value on Over at -125 on Hard Rock, but don’t like the idea of taking a 38-year-old pitcher who has missed 2.5 months due to injury.

In fact, none of the top four projected strikeout pitchers have a line Under 6.5, so you have to go to Detroit’s Jack Flaherty to find an enticing Over. FanDuel is offering Over 4.5Ks at -122 this morning. Flaherty’s line is low because the last time he faced Kansas City was his last start on  Aug. 24, and he got shelled, allowing eight earned runs in five innings with only three strikeouts. While he averages 1.3 fewer strikeouts in road starts than at home, Flaherty still averages a strong 5.6 punchouts on the road and a solid 7-4 Over 4.5 record. Before his last bad outing Flaherty pitched seven scoreless innings with nine strikeouts against Houston. Let’s hope that’s the Flaherty we see tonight.

MLB home runs, stolen bases, strikeouts cheat sheet

The SportsLine Projection Model was developed and is powered by the Inside the Lines team. You can find all of the team’s picks and content at our blog, which has all our personal best bets for free. The system is simple: We take the strongest SportsLine Model projected values vs. the best available prices at the time we publish our content. In most cases, lines move in our direction, so you should bookmark the blog, follow us on social and make it a habit of checking for updates throughout the day to maximize your expected value. 

The table below shows today’s projected leading home run, stolen base and strikeout leaders. We include the projection, and for HRs and SBs, the money line we’d set for YES HR/SB. You can use this cheat sheet to compare it to your book’s line, and if your book’s line is significantly higher than ours (and you like the player), then you would want to consider that bet.