First pitch is 7:10 PM PT for the middle game of the weekend series, and the rotation picture is the whole story here. Garrett Crochet is still in the early throwing-program stage of his shoulder/lat rehab, Kutter Crawford and Tanner Houck are both on the 60-day, and Patrick Sandoval is still on a rehab assignment in Worcester. Whichever arm Chad Tracy runs out Saturday is doing it without the team's actual ace backing him up later in the series. Seattle's pitching outlook is the opposite kind of story. Bryan Woo just went 7 strong in a 3-1 win over Baltimore to start this homestand, and the rotation has generally been the thing keeping the Mariners afloat while the lineup deals with its own injury list. If Boston catches Woo or anyone in that orbit Saturday, this is the kind of spot where a one-run grinder turns into a long night fast. The vibes around Boston are bad and getting worse. They followed a feel-good Rangers series win at Fenway by getting punched in the mouth 6-1 by Toronto on Tuesday, and they're now 29-41 with the front office still working through the Alex Cora fallout from April. Tracy is 2 months into the interim gig and the roster keeps getting thinner — Trevor Story just had sports hernia surgery, Roman Anthony can't swing a bat yet, and Romy Gonzalez is only just starting a rehab assignment in Portland. Seattle isn't exactly cruising either. Randy Arozarena (hamstring) is on the 10-day, Josh Naylor (shin/wrist) and Luke Raley have both been in and out of the lineup day-to-day, and Matt Brash is down with a Grade 1 lat strain. But the Mariners have one massive equalizer the Red Sox don't: Cal Raleigh is locked in, the rotation has held up, and they already showed earlier this season what they can do to this Boston pitching staff when things click. Saturday's series opener weekend has all the markings of a home team's spot. This is also a textbook get-right window for a Mariners team trying to stay in the AL West race after dropping 3 of 4 to the Nationals on the road last week. Boston has been one of the league's most beat-up teams for two months running, and the schedule isn't doing them any favors with a cross-country trip into a place that's traditionally been a house of horrors for visiting AL East offenses. Saturday night under the lights at T-Mobile is exactly where you'd circle a Seattle bounce-back.