But the Mariners also are sorting out a starting rotation that has seen Michael Pineda, Doug Fister and Erik Bedard traded away since last July. They're figuring out a bullpen that has added a number of interesting pieces.
And they're solidifying plans for who will fill the bill at third base, how Jesus Montero will split his time between catcher and designated hitter, who is going to handle the utility-infielder role and how exactly the lineup will shake out now that manager Eric Wedge has determined Ichiro Suzuki will be his No. 3 hitter.
Wedge has 20 days to toy with all those issues before the team boards a plane for Tokyo on March 22. The Mariners and A's can each take 30 players on that trip, but they must designate a chosen 25-man roster before the regular-season games at the end of that eight-day trek.
The accelerated schedule requires the Mariners to get two starting pitchers ready a week ahead of normal, and Wedge settled quickly on returning veterans Felix Hernandez and Jason Vargas. But the final three rotation spots remain in flux, and that sorting process begins with Blake Beavan on the hill for Friday's opener.
Beavan, 23, had a solid rookie season when he went 5-6 with a 4.27 ERA after a midseason callup, but he's in a battle with Hector Noesi, Hisashi Iwakuma and Kevin Millwood for the final three rotation berths.
"I know I don't have a definite spot," Beavan said. "I don't think I've earned that yet, but I feel good about where I am and I just want to go out and compete and throw strikes. That's what I do. I don't have nasty stuff like some of the other guys, but if I just throw strikes and go out and compete, everything else will take care of itself."
Noesi, acquired from the Yankees in the Pineda-Montero trade, will start Saturday against the A's in Seattle's Cactus League home opener in Peoria. Vargas will be on the hill Sunday in the annual charity game against the Padres in Peoria, with Iwakuma making his debut Monday against the Padres in what officially is a road game at the Peoria stadium those two teams share.
All those games begin at 12:05 p.m. and will be broadcast on 710 ESPN Seattle. The first game televised by ROOT Sports in the Northwest area will be March 14, although MLB.TV will show the Mariners-Angels game on March 7 from Tempe.
Hernandez threw in a simulated game on Thursday against Minor League batters at the Mariners' practice facility and won't make his Cactus League debut until the middle of next week.
Millwood, a 37-year-old veteran who signed as a non-roster invitee, will pitch in relief of Noesi on Saturday.
The Mariners' highly touted trio of young prospects -- Danny Hultzen, James Paxton and Taijuan Walker -- will all throw in a "B" game on Monday morning against the Reds in Goodyear, Ariz., before seeing their first Cactus League action later in the week.
That's a lot of sorting out still to do, which is why Wedge scheduled four intrasquad games already and will play several split-squad and "B" games as well in the coming weeks. Adding to the challenge is a bevy of relievers as the Mariners have 34 pitchers currently in camp.
That number doesn't include Stephen Pryor, 22, who left last week to deal with a personal issue and isn't expected back for a few more days. It does include left-handed veteran George Sherrill, who is the only pitcher not scheduled to throw in the next four days as he's continued to be brought along slowly.
After Beavan, the Mariners are expected to send Oliver Perez, Shawn Kelley, Cesar Jimenez, Steve Delabar, Chance Ruffin and Sean Henn to the mound on Friday.
Other questions will also start to play out in the coming days. Wedge has already said he'll give Chone Figgins the first crack at filling the leadoff role vacated by Ichiro. But it's not as certain where Figgins will play defensively. After working extensively at third early in camp, Figgins played some shortstop when Brendan Ryan was recovering from a sore arm and then moved to center field on Wednesday following Gutierrez's injury.
Michael Saunders and Casper Wells seem the more likely answers in center field in Gutierrez's absence, with Trayvon Robinson and non-roster invitee Darren Ford also in the mix.
Figgins and Kyle Seager have taken most of the reps at third base in camp, but the Mariners are also giving a good look to Vinnie Catricala, 23, who was last year's Mariners Minor League Player of the Year after putting up 25 home runs, 106 RBIs and a .349 batting average combined at Class A and Double-A.
Catricala didn't hurt himself by going 6-for-11 with a pair of home runs in the intrasquad games, though his defense remains a question.
Veteran Carlos Guillen also will work at third and first base, but the 37-year-old has been slowed by sore legs early in camp and didn't see any intrasquad action.