The Cardinals and Reds close out their series on Thursday afternoon at Great American Ball Park, and this one has a little something for everyone new to same-game parlays. St. Louis (65-63) sends Michael McGreevy to the mound against Cincinnati’s Brady Singer (61-66), and neither pitcher has been especially sharp lately. That combination of a shaky rotation matchup and a home underdog getting extra respect from the betting markets makes this an ideal spot to learn how a same-game parlay actually works.

A same-game parlay, or SGP, just means combining multiple bets from the same game into one ticket. All the legs have to hit for the parlay to pay out, but because you’re stacking smaller, connected ideas together, the payout is bigger than betting each piece on its own. Here’s a beginner-friendly three-leg SGP for Cardinals-Reds, with the reasoning behind each piece.

Leg 1: Reds Moneyline (+106)

Cincinnati enters as home underdogs, priced at roughly +106 on the moneyline while St. Louis sits around -114. That means a $100 bet on the Reds would return about $106 in profit if they simply win the game outright — you don’t need them to cover a spread, just cross the finish line first.

The number is closer than the Cardinals’ better overall record might suggest, and for good reason. Brady Singer has actually racked up more strikeouts per start than his counterpart this season (4.3 per game compared to McGreevy’s 3.8), and Cincinnati gets the benefit of playing at home. Betting models, including numberFire’s projection for this game, actually lean toward the Reds winning outright, giving Cincinnati a slight edge in the win-probability math.

Leg 2: Michael McGreevy Under 4.5 Strikeouts

This is the “beginner logic” leg — look at what a player has actually been doing recently, then bet the number that matches it, not the number the sportsbook hopes you’ll bet. McGreevy is averaging 3.79 strikeouts per game this season, comfortably below the 4.5 line most books have posted for Thursday’s start. His most recent outing against the Cubs was an outlier with six punchouts, but over a full season his strikeout totals have consistently landed below five.

McGreevy’s season includes a 3.48 ERA, which is respectable, but he generates outs more through soft contact and ground balls than swings and misses. That profile — a pitcher who works efficiently but doesn’t rack up strikeouts — is exactly the type of matchup where betting the under on Ks tends to hit more often than not.

Leg 3: Over 9 Total Runs

The total for this game sits at 9 runs, and there’s a reasonable case for the over here. Neither starter has been dominant this season — McGreevy sports a 3.48 ERA but has walked a fair number of hitters, while Singer is running a 4.66 ERA with a 5.03 xERA, a sign his results have actually been better than his underlying performance. Cincinnati’s team total alone is set at 4.5 runs, meaning the books already expect the Reds’ offense to do plenty of scoring on its own.

Add in two bullpens that will need to cover a decent number of innings once both starters get to the five- or six-inning mark, and the pieces are in place for a game that clears the total rather than turns into a pitcher’s duel.

The Full Parlay

Put together: Reds Moneyline (+106), McGreevy Under 4.5 Strikeouts, and Over 9 Total Runs. Combined, a three-leg parlay like this typically pays out in the neighborhood of 6-to-1 to 8-to-1 depending on your sportsbook — always check your book’s exact live odds before placing it, since prices shift throughout the day. Each leg on its own is grounded in something real: a competitive moneyline price, a strikeout rate that doesn’t match the year-long trend, and a total built around two pitchers who haven’t missed many bats or limited many runs in 2026.

That’s really the whole approach to building a smart SGP as a beginner — find two or three things you can explain in one sentence each, and stack them together. This Cardinals-Reds matinee gives you a clean example to practice that logic on.