The Mariners will keep their immediate reinforcements as close by as humanly possible. On Wednesday, the club announced that it will host its alternate training site at T-Mobile Park this year, making them the only team in the Majors to host its alt site exclusively at its big league ballpark.

Last year, the team used Triple-A Tacoma’s Cheney Stadium, which was originally believed to be the plan again for 2021. But weather played a huge part in the decision, given the regular rain that the Pacific Northwest sees in April and the retractable roof at T-Mobile Park.

By keeping the big leaguers and the alt site players under one roof -- literally -- the Mariners will have a number of logistical hurdles as well. Due to health and safety protocols, alt site players will have to conduct their training, workouts and sim games before the Major Leaguers arrive at the ballpark. The Mariners play 12 of their 28 games in April at home, and three are slated for 1:10 p.m. PT starts.

“They’ll be in there at odd times,” Mariners manager Scott Servais said. “It'll be in the early in the morning if we have a night game, and we have a day game, they could be in there early the evening or something like that. Certainly we go on the road, it's all open up at that point. So it made the most sense, just from logistics and the weather and the facility, everything included, to just have the guys there at T Mobile.”

The alternate sites are back this year due to the postponement of the Triple-A season to May 6, which was announced earlier this month. All Minor League seasons will now begin the first week of May.

Another hurdle specific for Seattle is that alternate sites will be permitted to schedule exhibition games with other clubs. Many of the Southern California teams (Angels, Dodgers, Padres) are in talks to do so. But with Seattle’s distant proximity from the rest of the league -- even if the Mariners opted for Tacoma -- it was always going to be an insurmountable challenge. That’s why the Mariners also considered using their Spring Training facility as their alt site, like many other clubs that train in Arizona. 

“We don't have that luxury, just because you have to stay close enough to the Major League team within driving distance,” Servais said. “We don't have a team close enough up there and Pacific Northwest, so it'll create a few more challenges. But again COVID has created all kinds of challenges for everybody.”

Players housed at alternate training sites will be those needed immediately for injury and backup purposes, which is why many top prospects have been reassigned to Minors Spring Training. Servais anticipates that the Mariners will have 20-25 players at their alt site. 

Dunn turns in final audition
Justin Dunn had up-and-down results in his final case for the sixth spot in Seattle’s rotation. Specifically, two at-bats in Wednesday’s 6-2 loss to the Cubs that he said he’d like to have back.

The first was a leadoff walk to Eric Sogard in the first inning, which he was able to get away with unscathed despite loading the bases. The second was a solo homer to Cameron Maybin on a breaking ball as part of a four-run fourth inning.

Dunn walked three for the second straight outing and had nine total over 11 innings in Spring Training. The big positive: Seven strikeouts among the 20 batters he faced on Wednesday.

Lefty Nick Margevicius, who will make his final spring start on Thursday against Oakland, is the other rotation candidate.

“It's fun. I mean, it makes it a lot of fun for Marg, too,” Dunn said of the competition. “We worked out together all offseason. So we were pushing each other all offseason and now pushing each other here. So no matter what, I mean, starter, reliever. It doesn't matter to me. I just want to be one of the best 26 in camp and help this team win ballgames.”

Raleigh reassigned to Minors
Switch-hitting catching prospect Cal Raleigh will be in the Majors sooner than later, but probably not until the Mariners need reinforcements for Tom Murphy and/or Luis Torrens. Seattle’s No. 8 prospect was reassigned to Minor League Spring Training ahead of Wednesday’s game against the Cubs, along with fellow catcher José Godoy.

Raleigh went 5-for-19 in Cactus League play, but he drew rave reviews from coaches and Mariners manager Scott Servais throughout camp for his acumen, ability to gameplan and guide even the most veteran pitchers. No. 1 starter Marco Gonzales touted Raleigh after the left-hander’s best Cactus League outing against the Rockies on March 13.

• Raleigh's power potential excites Mariners

In his last full season in 2019, Raleigh led all Minor League catchers with 29 homers in 121 games between Class A Advanced and Double-A. After Minors camp, he’s likely set for a high Minors affiliate, and Mariners management has repeatedly said that they anticipate Raleigh will be in the big leagues at some point in 2021.

Paxton won’t pitch in another Cactus game
James Paxton’s Cactus League run is likely over after just one start, a stellar outing in which he struck out eight in 4 1/3 innings against the Brewers’ “A” lineup on Sunday. "Big Maple" is on turn to pitch again Saturday, but Seattle’s opponent -- the Giants -- is also who Paxton will face in his first outing of the regular season in either the second or third game.

Instead of giving San Francisco an early preview, the strategic decision is to have Paxton pitch in another “B” or intrasquad game, depending on whether the Mariners can find an opponent to wrap his Spring Training.

Yusei Kikuchi will also pitch in a backfield game for his final outing on Friday, while Gonzales starts against San Diego. Chris Flexen will pitch in the Cactus League finale on Monday, but on an abbreviated term in order to finish stretching out the bullpen arms.

Opening Day sells out
The Mariners will have a capacity 9,000 on hand when they open the regular season next Thursday in SoDo. The club announced Wednesday that Opening Day sold out before tickets went on sale to the general public due to the first priority to season-ticket members and Mariners Mail subscribers.

There are tickets remaining for the other 10 games in the first two homestands against the White Sox, Astros and Dodgers. Tickets for those games go on sale on Thursday at 10 a.m. PT, available exclusively at Mariners.com/tickets. The club has not released tickets for sale beyond that point.