Seattle Mariners (Bryan Woo) at St. Louis Cardinals (Matthew Liberatore) Prediction & Betting Pick | MLB April 25, 2026

📅 Date: Saturday, April 25, 2026
🕖 Time: 2:15 PM EST
🏟️ Venue: Busch Stadium - St. Louis, MO

This is one of those spots where the number and the matchup line up almost perfectly. You’ve got a high‑end arm in Bryan Woo, a flawed but serviceable starter in Matthew Liberatore, a pitcher‑friendly park in Busch, and a Seattle lineup that’s been dragging on the road. When you put all that together, it points straight at a slow, controlled first five rather than any kind of early shootout.

Let’s start with Woo, because he’s the anchor of this play. A 2.25 ERA, 0.88 WHIP, and zero home runs allowed over 32 innings is big‑time work. Twenty‑two hits and just six walks in that span tell you he’s not giving away baserunners, and 26 strikeouts show he’s missing enough bats to escape jams when he needs to. His career profile backs it up too — 3.14 ERA, 0.97 WHIP, and only 7.0 hits per nine across 427 innings. That’s not a small sample; that’s a legit track record of suppressing damage.

Seattle’s overall pitching numbers mirror what Woo is doing. The Mariners sit 4th in MLB with a 3.42 ERA, carry a 1.22 WHIP, and own a strong 3.44 K/BB ratio. They’ve allowed just 20 home runs and 88 earned runs all season. This is a staff built to keep games in the low‑to‑mid scoring range, and they’ve had to be that way because the offense hasn’t carried its weight. When you’re backing an under, you want a team whose identity leans toward grind‑it‑out baseball, and that’s exactly what Seattle is right now.

Offensively, the Mariners are doing us a favor. They’re hitting .226, slugging .363, and averaging just 3.9 runs per game (25th in MLB). They’ve struck out 236 times already, and while they’ve hit 25 homers, the overall profile is streaky and inefficient. On the road, it’s been even uglier — a 1–8 record away from home tells you how often the bats have gone missing. That’s a big reason I’m not scared off by Liberatore’s flaws; this isn’t a lineup that’s been consistently punishing mistakes, especially in someone else’s park.

Liberatore’s surface numbers are a mixed bag, but they’re workable for this angle. A 3.67 ERA over 27 innings with a 1.41 WHIP, 28 hits, 10 walks, and five homers allowed isn’t clean, but it’s not a disaster either. He’s more vulnerable than Woo, no question, but he’s also facing a lineup that’s been below average in almost every offensive category. If there’s a spot where Liberatore can get through the order once or twice without getting blown up, it’s this one.

St. Louis’ offense is better than Seattle’s, but it’s not some juggernaut that scares you off an under. The Cardinals are hitting .229, with a .321 OBP, .375 slugging, and 4.67 runs per game. They’ve hit 27 homers and driven in 109 runs, which is solid, but not overwhelming. Against a pitcher like Woo, who doesn’t give up the long ball and limits hard contact, they’re more likely to be forced into stringing hits together — and that’s tough against a guy with his command and strikeout ability.

Busch Stadium itself leans our way too. It’s not a launching pad, especially in a day game. The park suppresses power to the gaps, and pitchers can be more aggressive in the zone knowing mishits don’t automatically turn into extra‑base damage. For a guy like Woo, who’s already keeping the ball in the yard, that’s a nice bonus. For Liberatore, it gives him a little more margin for error against a light‑hitting lineup.

Seattle’s defense also quietly helps the under. They’ve converted 68% of balls in play into outs, and their .988 fielding percentage (7th in MLB) with 31 double plays turned shows they’re not giving away extra outs. Clean defense is huge for first‑five unders — you don’t want free baserunners or extended innings because someone booted a routine grounder. The Mariners have been sharp in that area.

The one concern on paper is St. Louis’ bullpen and overall pitching numbers — 4.77 ERA, 1.43 WHIP, and a 4.80 FIP — but that’s exactly why we’re isolating the first five. We’re not asking the Cardinals’ staff to hold up for nine; we’re betting on Woo to be himself and Liberatore to be competent for a couple of trips through the order. Once the bullpens get involved, all bets are off — and we’re already off the hook by then.

So the way I see it, we’ve got: an ace‑level arm in Woo, a below‑average Seattle offense, a Cardinals lineup that’s good but not elite, a park that suppresses power, and a game script that leans toward pitching over fireworks. That’s exactly the profile I want when I’m laying a first‑five under at 4.5.

📌 Official Pick
Under 4.5 First 5 Innings -138