Of course, there will be days when Carlos Ruiz starts at catcher and others get days off. And Heredia certainly isn't a lock as the backup in left field, where Dyson will likely start against some lefties and quite possibly on Opening Day when the Astros will likely go with southpaw Dallas Keuchel.
National media is saying that the Mariners' Minor League system is in very poor shape with few, if any, prospects in the wings. What is your take?
-- Ken M., Okanogan, Wash.
A few years ago the Mariners were projected to have one of the best Minor League systems. They had a lot of highly-regarded prospects, but few of those guys have made an impact. Still, Minor League rankings are interesting, but they're not all-knowing. No one was talking about Edwin Diaz as an elite prospect last year, and he wound up being one of the best rookies in the Majors.
My take is the Mariners do have a couple high-level prospects in Kyle Lewis and Tyler O'Neill, as well as several rookies on their roster who are expected to play a lot this year in Vogelbach and Haniger. Mariners general manager Jerry Dipoto has been able to use his Minor League system to acquire talent in trades. But they do need to start hitting on high Draft picks in order to cultivate more homegrown talent.
Will we see more home runs out of Cruz or stolen bases from Dyson in 2017?
-- Kyle F., Soldotna, Alaska
An interesting prop bet. Cruz has averaged 42 home runs over the last three years, while Dyson has averaged 31 stolen bases over the same span in Kansas City. While that would seem to favor Cruz, I'm going out on a limb and taking Dyson because I think he's going to play more this season than he did in his part-time role with the Royals. I also think the Mariners are going to be eager to put their new speed threat to use atop their lineup.
Do you think Felix Hernandez will throw normal bullpen sessions between starts this season?
-- Jonathan D., Emmett, Idaho
Good question, and I'm not sure we'll know the answer until the regular season begins and Hernandez sees how he's feeling and producing on the mound. In the past, he preferred less strenuous flat-ground throwing sessions between starts. But pitching coach Mel Stottlemyre Jr. pushed him to throw a few bullpens toward the end of last season, and it'll be interesting to see if Hernandez feels he needs to change his routine now as he's getting older and where that goes in '17.
As an overseas fan -- and with the NFL thriving over here and the NBA and NHL both having played here, as well -- do you think Major League Baseball will follow suit with its own international series?
-- Shaun J., Bedford, England
MLB has played some international series in the past, the most recent being when the Mariners opened their 2012 season in Tokyo against the A's and the Dodgers and D-backs faced off in Sydney, Australia in 2014. There also have been exhibition games in Mexico and Cuba since then, and I've seen talk of trying to get some games in London.
Obviously travel and timing are the biggest challenges for regular-season games. It's difficult to squeeze an overseas trip into a 162-game schedule that only features a few days off each month. That's why the international series have been held at the start of the season -- in Seattle's case, they played two exhibition games and the two-game series against the A's in Japan and returned to Arizona for a week of Spring Training before resuming regular-season play as normal.
Some have mentioned a change in the strike zone this year, which would take away the low strike. I hope they're wrong. Is this a definite change, a proposal, or just a rumor?
--Dan K., Sydney, Australia
Major League officials have indeed at least talked about raising the bottom of the strike zone to the top of the knee, though that is an issue that would have to be approved by the MLB Players Association. The belief is that by forcing pitchers to come up in the zone, hitters will put more balls in play and the result will be more action and quicker games. That is a matter of some debate, however, and it seems a tough challenge to get anything changed prior to this season.
Will the Mariners bullpen look the same come All-Star break time? Who do you see having breakout years?
-- Sean Q., Ellensburg, Wash.
Last year's bullpen had a near-complete makeover by midseason due to injuries and poor performance, but I would expect less midseason turnover this time. That said, bullpens are usually the most volatile part of any roster. Shae Simmons, a right-hander acquired from Atlanta, could be a surprise, and Dan Altavilla could be poised for big things after his strong September. Thyago Vieira is this year's potential power arm from Double-A, if he can control his 100-mph fastball, while Tony Zych might be a bounceback candidate if he's recovered from last year's shoulder issues.
Greg Johns has covered the Mariners since 1997, and for MLB.com since 2011. Follow him on Twitter @GregJohnsMLB and listen to his podcast. This story was not subject to the approval of Major League Baseball or its clubs.