SEATTLE -- After a breakout season in 2017, Yonder Alonso isn't sure where he's headed as he hits free agency for the first time this offseason. But the 30-year-old first baseman certainly would welcome the chance to return to the Mariners after playing the final seven weeks of the season in Seattle.

"I love it here," Alonso said. "It's awesome, a first-class group, and they treated me well. I'd love to be back here. I think the future here is very bright, and we're very close to winning, and I would definitely want to be a part of that.

"I think all the guys here know how much I appreciate this place and want to be here and obviously play here. But I'm going to have options and different scenarios and situations, so we'll see what it holds."

Alonso had never hit more than nine home runs in a season during his time with the Reds, Padres and A's from 2010-16, but he busted loose with 28 homers and a .266/.365/.501 line this year. He was an American League All-Star for the A's, then was acquired by Mariners executive vice president and general manager Jerry Dipoto in mid-August for outfielder Boog Powell to provide another solid left-handed bat for an attempt at a late-season push.

Dipoto said at the time that the acquisition would also give Seattle a first-hand look at a guy who might be part of a longer-term solution at first base as well. And after Alonso hit .265 with six homers and 18 RBIs in 132 at-bats for Seattle, Dipoto now says he's "a strong consideration" among a pretty flush group of available free-agent first basemen, which also includes Lucas Duda , Mitch Moreland, Logan Morrison , Carlos Santana and Mariners teammate Danny Valencia.

"Yonder did a nice job for us," Dipoto said. "First of all, I think he's a good guy in the clubhouse, and we got to experience that. He shows up to work every day. He hits right-handed pitching. He did that for us. Maybe it was a little streakier than it had been in Oakland, but I want to say it's about 15-18 percent better than the league average. He plays a pretty solid first base. I think he gave us a presence after we got beyond the middle of our order. "

Alonso believes there's more in the tank after he made a strong step forward this year.

"I feel good about my season," he said. "But I look at my numbers, and I wasn't surprised. A little part of me feels there's so much room to develop and get better. I felt like I made good adjustments to what guys were doing against me. Now I have an idea where those adjustments are at, and it feels good to finish strong. I feel like I did that."

Alonso said he learned about the Mariners at the same time they were learning about him. And he liked what he saw.

"I think we're very close," he said. "This team has a lot of resilience, a lot of no-quit, fight-to-the-end. It was a lot of fun to be around here. In Oakland, they lost a lot of games and that was tough, grinding. But being a part of these guys for a month and a half, I smelled the winning environment and what winning is all about, the confidence every single day, and that means a lot."

Alonso was born in Cuba and grew up in Miami. He carries the nickname "Mr. 305" as a tribute to his Miami area code and roots. But while Miami is a long way from Seattle, that isn't a part of his concerns as he prepares for the start of free agency, which begins after the completion of the World Series.

"I don't care about that," he said. "I've lived on the West Coast my whole career. I started my career in San Diego. My wife is from Redding, Calif., and her whole family is on the West Coast, so that doesn't matter to me."