A year ago, the six-foot, 210-pound Seager hit in the middle of the lineup and led Seattle with 20 home runs and 86 RBIs. But that role could change this season with the addition of the mammoth Michael Morse, who is living up to his "Beast" nickname at 6-foot-5, 245 pounds, as well as Kendrys Morales (6-foot-1, 225 pounds).
Add in Raul Ibanez and Jason Bay, as well as returning players Justin Smoak, Michael Saunders and Jesus Montero, and the Mariners have increased power potential up and down their lineup.
"We feel we've got three or four veteran guys that could be in the middle of our lineup and we've got some young guys that don't necessarily have to be there from Day 1, but are capable of doing that in the future," manager Eric Wedge said. "They've gained some experience at that already by necessity.
"It's not just the veteran presence. That was something we wanted to have, but we brought these veterans in to contribute. We brought these guys in here to help us perform and win ballgames."
Morse and Morales didn't take long to display their power when they put on a nice show in the first round of batting practice, both clearing the outfield wall with frequency and Morse ripping one moon shot over the 25-foot batter's eye above the center-field fence 410 feet away.
"That's always good," Morse said with a smile after finishing up the first day with some conditioning drills.
Morales said he felt welcomed by the Mariners after being acquired from the Angels in an offseason trade for Jason Vargas. More importantly, he said he felt healthy.
Morales missed all of 2011 with a fractured left ankle and came back to hit .273 with 22 home runs and 73 RBIs last season, picking up considerable steam in the second half. He says there's a big difference in his situation this spring.
"It's a radical change because I couldn't do things and run at 100 percent or anything [last year at this time]," Morales said. "I couldn't exercise with much strength."
Morales worked alongside Smoak at first base during infield drills. Dustin Ackley was alone at second on the same field, while Brendan Ryan and newcomer Robert Andino split time at shortstop and Seager and Alex Liddi took grounders at third.
Seager, 25, said the influx of veterans has changed the clubhouse atmosphere already.
"It's definitely an experienced feel," he said. "You've got a lot of guys in there, especially on the position side now, that have been around a long time and have had success for a lot of years. So there's definitely a lot to be learned."
The Mariners are counting on some of their young position players to blossom with a year under their belt, with Montero, Seager and Ackley now entering their second full seasons. Additionally, Franklin Gutierrez could be a huge boost if he stays healthy in center field.
"It's always exciting the first day when you come to Spring Training, just seeing your friends and everybody is excited to start practicing," Gutierrez said. "This is the beginning of everything. It's a long season and we're starting today.
"There are a lot of new faces, new guys," said Gutierrez. "I think we have a really good team. We're just trying to prepare to win this year. We have some good additions, so let's see what happens."