JUPITER, Fla. -- As Spring Training's final week began, Marlins general manager Kim Ng noted that final roster decisions will likely go down to the wire, in particular the starting second baseman.

Jazz Chisholm and Isan Díaz have split reps at second this spring, with Jon Berti seen as more of a super-utility player. Chisholm, MLB Pipeline's No. 66 overall prospect, has been surging of late, going 6-for-his-last-13 with two homers, four runs, three RBIs, his first two walks and four strikeouts. He singled and scored as the starting shortstop in Monday's 7-2 win over the Cardinals at Roger Dean Chevrolet Stadium.

Díaz, who entered the game in the seventh inning, is 2-for-25 with six walks. Entering Monday, however, he has an average exit velocity of 92.9 mph. That ranks third among Marlins with at least 10 batted balls in play recorded by Statcast. Chisholm is second, at 93.6 mph.

"I think these are two very good players," Ng said during a Zoom call on Monday morning. "From what I heard this offseason, both have shown as advertised. Isan's been a guy that put himself in a lot of good counts, hasn't quite gotten the results that you'd like to see. I think some of that has just been bad luck, and I think he's hit the ball hard, and so you probably aren't going to see it show up in the numbers and the statistics.

"But he's done a good job at second base out in the field. In Jazz, obviously, I think we all see the athleticism there. Had the home run yesterday, and so it seems like he's turned it up a notch."

Chisholm, 23, made his MLB debut in 2020, making 21 appearances and posting a .563 OPS while skipping the Triple-A level. Díaz, meanwhile, had a breakout season at Triple-A in '19, slashing .305/.395/.578 before receiving a callup. A former top prospect, the 24-year-old has 56 big league games of experience.

The player not selected to be the starting second baseman will begin the season at Triple-A Jacksonville.

"There are many players that have come up to the big leagues, struggled, gone down to Triple-A and just prepare themselves," Ng said. "That's what we think: Either of these guys -- if they're the ones that have to go down -- are going to have to get their reps, get their at-bats, work on their game planning. Just be prepared whenever that call comes."

Among the other topics Ng addressed on Monday:

Rule 5 selections

Right-handers Paul Campbell and Zach Pop have a week to make a good impression or else be returned to their original clubs. In order to stay with the organization, they must be on the active roster. According to Ng, the Marlins are still mulling whether to go with eight or nine relievers to open the season. Barring an injury, Anthony Bass, Yimi García, Dylan Floro, John Curtiss, Adam Cimber, Richard Bleier, Ross Detwiler and James Hoyt are projected to have spots. Should Miami go with an extra arm, that would leave just one open space.

Campbell, who got a late start in Grapefruit League play because he was away from camp for a personal issue, has pitched three scoreless and hitless innings. After striking out four across two frames in his debut last Tuesday, he walked the bases loaded on Saturday but didn't allow a run. Ranked as Miami's 29th prospect per MLB Pipeline, the 25-year-old could project as a multi-inning reliever.

Pop, a former top prospect with the Orioles before undergoing Tommy John surgery in 2019, has shaken off the rust after spending 23 months away from a game mound. The 24-year-old has thrown four scoreless outings, including the sixth inning on Monday. After a leadoff walk, Pop retired Yadier Molina, Dylan Carlson (MLB Pipeline's No. 13 overall prospect) and Austin Dean. Last Thursday he reached a maximum velocity of 97.9 mph. Manager Don Mattingly recently called Pop's two-seam/slider mix "big league stuff."

"Out of Pop, we've all seen that his stuff is just excellent," Ng said. "Campbell, he came out [for] his first outing and I think pleasantly surprised all of us in terms of not just the stuff but I think the wherewithal and what he was able to do in that game. I think you saw in his last outing a little bit more hesitancy. But in terms of the both of them, really surprised and happy about where they both are. We need to see more of them; obviously we have tough decisions coming up, and we're going to try and see them at least a couple more times before this is all over."

Outlook on prospects

Ng, who took over GM duties in November, has often been seen sitting behind home plate during Grapefruit League games or standing on the back fields at the Roger Dean Chevrolet Stadium complex. At the beginning of Spring Training, she expressed her eagerness to see Miami's system -- which was recently ranked fourth best by MLB Pipeline, in person.

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"I would say that these guys came as advertised," Ng said. "Having heard so much about them this offseason, as a whole, what I saw was great athleticism. [You] understand why they are where they are. But as we move forward, we just felt like they needed to go down, and we need to obviously start preparing now with a week to go to get to Opening Day. But I saw great athleticism. Monte Harrison, [José] Devers was a really interesting guy for us. [Jerar] Encarnación [has] tremendous power, and we've got him working out at first base to add to his versatility. So again, very happy with these guys."