Pittsburgh Pirates vs San Francisco Giants Prediction, Odds and Picks for Today, 05/09/26

The Pittsburgh Pirates and San Francisco Giants square off with a pair of quality arms on the bump to get this matchup started. For Pittsburgh, right-handed pitcher Braxton Ashcraft (3.02 ERA, 1.08 WHIP) gets the start coming off 7.2 scoreless innings of work against the Reds. For San Francisco, Landedn Roupp (3.18 ERA, 1.06 WHIP) gets the starting nod with some incredible underlying figures to his name. In fact, both starters rank highly in several advanced stat categories; both pitchers hold exactly a 2.64 xERA (89th percentile) and sit in the top fifth of the league in xBA, strikeout rate and pitching run value. 

On the other side of things, the Giants’ offense has been putrid against righties like Ashcraft, ranking 29th in MLB with a 80 wRC+ mark against RHP. The Pirates have certainly produced better results with the bat in hand, but San Francisco has a definitive advantage when the bullpens enter the equation, posting a 3.35 combined ERA as a unit (6th in MLB). On top of everything listed already, roughly 75% of public bets are siding with the over at the time of publishing, and I’ll gladly fade the public and take the under in this spot.

Pirates vs Giants prediction: Under 7.5 (-110) at time of publishing. Playable to (-120). 

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