After a three-game slate yesterday, MLB is back with all 30 teams in action. As we dig deep toward the end of the season, the playoff race is heating up and there are a few prediction market props that stood out to me.
Check out my favorite MLB player prop picks today for Tuesday, September 22.
MLB Player Props Today
- Chris Bassitt Under 16.5 Outs Recorded
- Sean Manaea Over 4.5 Strikeouts
- Michael King Under 4.5 Hits Allowed
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Blue Jays vs Orioles Player Prop
Chris Bassitt's entire 2026 has been defined by short outings. He opened the year battling command in Baltimore's rotation and never strung together the deep-innings track record he built in Toronto.
Over his first several turns back in April, he was pulled before finishing five innings in start after start , and after a back injury shelved him in June, the Orioles have understandably kept him on a tighter pitch-count leash since his August return.
That's the headline for Bassitt. This is a 37-year-old on a $18.5M "innings-eater" deal who, in practice, has been anything but this season.
Bassitt already faced this exact Blue Jays team on September 11 and worked exactly 5.0 innings. He allowed plenty of traffic (bases loaded, two outs, third inning) and needed 95 pitches to get through five frames, allowing 2 ER/6 H/3 BB. That start is the single best data point available for tonight's number, and it lands a full out below the line.
He remains a soft-contact/ground-ball pitcher (career GB% in the mid-40s, 80th-percentile hard-hit rate, 85th-percentile exit velocity allowed) rather than a swing-and-miss arm. That profile keeps him around a lot of balls in play and traffic on the bases, which inflates pitch counts and shortens outings rather than letting him cruise deep into games.
Lastly, both Baltimore and Toronto are scrapping for the final AL Wild Card spots in the season's last two weeks. In pennant-race baseball, managers pull starters early at the first sign of trouble rather than let a rope play out, which works against a guy who already needed 95 pitches to finish five innings against this same lineup 11 days ago.
Pick: Chris Bassitt Under 16.5 Outs Recorded (Kalshi)
Mets vs Rangers Player Prop
The case here is about regression to a real, elevated season-long rate, not the eye-test from his last two outings. Manaea's full-season strikeout profile is strong: a 23.5% K rate, 23.9% whiff rate, and a K/BB right around 3.00 with a K/9 approaching 9.4.
That is comfortably above the 4.5 threshold on a per-start basis. A pitcher running a 9+ K/9 over a full season needs only five innings to clear this number on average, and Manaea has gone 5.2 IP in each of his last two turns.
Manaea has topped 4.5 strikeouts in the clear majority of his starts this year; two low-punchout games in a row is well within normal month-to-month variance for a pitcher with this K rate, not evidence of a permanent decline in stuff.
The matchup supports the bounce-back too. Manaea's problem in 2026 has specifically been damage in the sixth inning and beyond (a 9+ ERA and .619 opponent average after the 5th), not swing-and-miss stuff. His four-seam/cutter combination has generated plenty of whiffs in the first four-to-five innings all season (.227 opponent average, .599 OPS through five).
Since strikeouts are likely to come early against the Rangers, not a sixth-inning problem against him, this prop is largely shielded from the exact flaw that's been dragging his ERA up.
Texas also isn't a contact-oriented, disciplined lineup that neutralizes strikeout stuff; they chase and swing-and-miss at an average-or-worse rate, which plays into a K/BB near three.
Pick: Sean Manaea Over 4.5 Strikeouts (Polymarket)
Padres vs Dodgers Player Prop
Michael King is having a legitimately excellent season by the exact metric this prop is built on. His full-season profile is elite contact suppression. A 3.45 ERA, a 1.20 WHIP, and, going back to 2025's percentile rankings that still describe his approach.
A mid-80s percentile ranking in average exit velocity allowed and an 80th-percentile hard-hit rate, all backed by an above-average ground-ball rate. That's a pitcher whose whole competitive edge is limiting hard, clean contact rather than missing bats in bulk, which is exactly the skill that caps hit totals start after start regardless of opponent.
The head-to-head history against these Dodgers is the strongest piece of evidence here. Earlier this season, King stifled this same lineup, going seven innings, allowing four hits, and striking out nine in a 1-0 win over Yamamoto. allowing exactly the number on this line against L.A.'s full-strength order, with room to spare on innings.
His current form supports the same shape. Over his last handful of turns, King has been trending toward exactly this kind of outing: He allowed five hits over seven innings against a Giants team that beat him up early before he retired 18 of 19 batters at one point, four hits allowed in six innings in a win over Atlanta, and surrendered only three hits in seven shutout innings against Houston earlier in the stretch.
San Diego is fighting the Dodgers directly for playoff positioning in their final head-to-head series of the year, which means King is being deployed as the Padres' top option to start this series. They are confident in him, and you can back him confidently as well.
Pick: Michael King Under 4.5 Hits Allowed (Kalshi)
