SEATTLE -- With a young core in place, a manager and president of baseball operations re-upped to multiyear contract extensions and an ambitious fanbase hungry for more following a 90-win season, this could be one of the more significant offseasons in Seattle in recent memory.

Mariners chairman and managing general partner John Stanton recently reiterated that the club will significantly increase payroll, which followed what Jerry Dipoto said at his end-of-season press conference. Yet there are still some internal housekeeping roster decisions that loom before the free-agency window opens.

• Mariners’ roster breakdown | 5 key questions this offseason

Here is a look at some of the key questions and dates surrounding the Mariners this winter.

Which players are free agents? And are any of them likely to receive a qualifying offer?
A qualifying offer is a one-year deal worth the mean salary of MLB's 125 highest-paid players, which this year is valued at $18.4 million. The Mariners don’t have any players that they would target for a QO this offseason. Below is the list of their free agents and each’s situation:

• LHP Tyler Anderson: Mariners manager Scott Servais has publicly expressed his desire to bring back the lefty, who helped fortify a rotation that desperately needed him for the final two months of the season. The 31-year-old makes a lot of sense for Seattle’s needs this winter and he shared some mutual admiration, too. But after pitching on one-year deals over each of the past two years, it’s likely that Anderson will seek -- and get -- a multiyear contract.

• LHP Sean Doolittle: Doolittle plugged some low-leverage innings for Seattle down the stretch, but given that he’s 35 years old and relies on one pitch, it’s not likely that the Mariners bring him back.

• LHP James Paxton: Bringing back Big Maple on a low-cost deal makes a lot of sense for both the veteran, who can re-establish his value at 33 years old, and the team, which if last year was any indication, could benefit from as much starting pitching depth as possible. The Mariners got a hometown discount on a one-year, $8 million deal last year before he underwent Tommy John surgery immediately after his 2021 debut. Yet Paxton was a constant presence at T-Mobile Park throughout the season, serving as a veteran mentor while completing his rehab.

• LHP Héctor Santiago: Santiago is in the midst of an 80-game suspension he received for performance-enhancing drugs.

• RHP Joe Smith: The 37-year-old is MLB’s most-tenured active pitcher, with 832 appearances. He was solid for Seattle after coming over in the Kendall Graveman trade, posting a 2.00 ERA in 23 outings. But given the Mariners’ bevy of bullpen options, a reunion next year seems unlikely.

Which players have contract options, and what’s the impact on payroll?
The Mariners have two such players, both of whom Dipoto said they wouldn’t address until after the World Series:

• 3B Kyle Seager (one-year, $20 million club option): Given that Seager turns 34 on Wednesday, comes with a costly price tag and received an emotional send-off on the final day of the season, it seems all but certain that the Mariners will let him walk after 11 seasons in Seattle.

• LHP Yusei Kikuchi (four-year, $66 million club option OR one-year, $13 million player option): Committing to the club option once seemed certain, especially as Kikuchi was pitching his way to his first All-Star bid in the first half. Yet a second-half spiral that cost him his rotation spot during the final week amid a playoff push. He’ll almost certainly elect his player option, unless he were motivated to return to Japan, where he pitched for nine seasons.

Which players are eligible for salary arbitration?
Players with between three (in special cases, two) and six years of service time are eligible for arbitration -- a process in which they exchange salary figures with their club and, if they can’t find middle ground, consent to an independent arbiter’s decision. Below are the players that fall into this category, along with projected salary figures from Cot's Baseball Contracts:

• RHP Diego Castillo (first year, $1.75 million)
• SS J.P. Crawford (second year, $4.5 million)
• OF Mitch Haniger (third year, $8 million)
• UTIL Dylan Moore (first year, $1.5 million)
• RHP Casey Sadler (first year, $1.25 million)
• RHP Paul Sewald (first year, $1.7 million)
• RHP Drew Steckenrider (second year, $1.75 million)

Who might be a non-tender candidate?
Moore is the most likely given that he’s set to earn a decent salary boost and is coming off a year in which he hit .181/.276/.334 (.610 OPS) with a 74 wRC+ (league average is 100). He’s proven to be valuable in a super-utility role, but the Mariners could have a 40-man roster crunch that would put his spot in jeopardy.

What are their needs this offseason?
A starting pitcher and an impact bat, possibly more than one of each depending on cost and fit. For all their success in 2021, the lineup proved to be a liability at times, albeit earlier in the season. Overall, Seattle hit .226/.303/.385 for a .688 OPS that ranked fourth-lowest in baseball. And this is with 35 homers and 100 RBIs worth of production from Seager, which they’ll now likely need to replace. All of it points to Seattle adding from outside to lengthen the lineup.

• Upcoming free agents, position by position

And though Seattle’s starting pitching was mostly solid and a huge catalyst during the second half, its depth was tested throughout the year due to significant injuries. The Mariners began the year with a six-man rotation to help govern their young pitchers’ workloads, but that sixth spot wound up being used as a bullpen day for extended stretches when Marco Gonzales and Justus Sheffield went down. Their pipeline is loaded with pitching, but they still need at least one or two arms to fortify the rotation.

“I'd like to see us add a couple players,” Servais said. “I don't think it's just one big fish, so to speak. I think it's a couple guys to balance out the lineup to create more length to our lineup, and I do think some help in the starting rotation is key.”

Who might they be willing to trade?
Any of their relievers could be on the table if it puts them in position to fill their most prominent needs. Bullpens can be fickle and Dipoto has had no reservations about dealing his highest-leverage arms to address immediate voids, such as the trade of Graveman for Abraham Toro in July, when Seattle badly needed a second baseman.

One has to think that given how much prospect capital the Mariners have, some of their Top 30 prospects -- aside from their top four of Julio Rodríguez, Noelvi Marte, George Kirby and Emerson Hancock -- could be in play, too, if it nets impact Major League talent.

Who needs to be added to the 40-man roster to be protected from the Rule 5 Draft?
Teams must reinstate players from the 60-day IL by five days after the conclusion of the World Series, and for the Mariners, that list includes starting pitchers Justin Dunn and Nick Margevicius, reliever Ken Giles, first baseman Evan White and center fielder Kyle Lewis.

As for the Rule 5 Draft, the deadline for prospects to be added to the 40-man to protect them from being taken by other clubs is Dec. 1, which will happen as scheduled because the current collective bargaining agreement doesn't expire until the end of that day. Among the Mariners’ Top 30 prospects that will be need to be protected are outfielders Julio Rodríguez (No. 1) and Alberto Rodriguez (No. 21) and right-hander Sam Carlson (No. 24).

Other names that aren't among the Top 30 that would need to be protected include right-handers Dayeison Arias and Devin Sweet, left-handers Ray Kerr and Brayan Perez, shortstop Jose Caballero and infielder Joe Rizzo.

Any other important dates to know?
The General Managers Meetings will take place from Nov. 8-11 in Carlsbad, Calif. The collective bargaining agreement expires on Dec. 1. The Winter Meetings are currently scheduled for Dec. 6-9 in Orlando. The international signing period closes on Dec. 15.