Now, the grind begins. The Mets have played nine games this season, with three off-days sprinkled in between. They’re about to play nine in a row before their next break, a stretch that should put some of their depth to the test. Before that happens, it’s time to dig once again into the Inbox.

With Brandon Nimmo’s early struggles at the plate, do you think Mickey Callaway will bat him lower in the order? If so, who do think is currently the best player to hit leadoff?
-- Sharon F., New Jersey

Given how Brandon Nimmo performed last season and toward the end of Spring Training, I think it’s in the Mets’ best interest to give him at least a few more games at leadoff before dropping him in the lineup. When Nimmo is right, he’s an ideal leadoff man, capable of posting sky-high on-base percentages with speed to boot. The Mets owe it to themselves to give him a relatively long leash.

If not Nimmo, the obvious alternative is Amed Rosario, the fastest Mets regular. Rosario led off frequently down the stretch last season, but his on-base percentages the past three seasons (including this one) are .271, .295 and .289. Without significant improvement there, he’s not New York’s best option.

The Mets tried Jeff McNeil at leadoff on Sunday, and they could do so again if Nimmo continues to struggle. An outside-the-box suggestion? How about Pete Alonso, who posted a career .381 OBP in the Minors?

Mostly, though, the Mets are at their best if Nimmo is batting leadoff and thriving. Any other option would be imperfect.

Why aren’t the Mets being more aggressive in pursuing free agent Dallas Keuchel, knowing Jason Vargas and Zack Wheeler could potentially be free agents next season?
-- Brian B., Sherman Oaks, Calif.

Since folks seemed unsatisfied with last week’s Inbox answer that the Mets aren’t in serious pursuit of Dallas Keuchel or Craig Kimbrel, we’ll revisit the topic. On the surface, Keuchel appears to be a snug fit: The Mets, unlike many teams, can commit to him in 2020 and beyond because their current rotation includes two impending free agents, without any big league-ready prospects waiting in the wings.

The price is the main issue. According to MLB Network’s Ken Rosenthal, Keuchel is seeking a one-year deal worth at least $18 million, or a multi-year contract with a lower average annual value. That’s a lot for a 31-year-old who showed some alarming trends last year, most notably a severe drop in strikeout rate. Scouts seem mixed on his future potential. And it’s a lot for any team to commit in mid-April, at a time of year when budgets tend to be set.

Still, Keuchel makes a lot of sense for a Mets team lacking much in-house rotation depth. I suspect New York is still sorting out what’s real and what’s not in its starting five, keeping tabs on Keuchel -- like a lot of teams -- in case he gets desperate. Should an injury or some other ill befall the Mets’ rotation, their interest would probably spike that that time.

Should we worry about Seth Lugo and Robert Gsellman? We’ve seen they are better than this.
-- Jim V., Texas

In Seth Lugo’s case, definitely not. Despite his early struggles, Lugo has demonstrated elite swing-and-miss ability this year. So far, his defense has done him no favors. He’s only appeared in five games, and he spent a good chunk of them pitching through illness. Lugo should be just fine.

Robert Gsellman is a little more troubling only because this has become a pattern. Dating to last August, he’s allowed at least one earned run in nine of his past 16 appearances, posting a 6.91 ERA over that stretch. Gsellman’s strikeout and walk rates have both been fine, suggesting his stat line could normalize soon. But the Mets need to see more from a player they’re counting on in 2019 and beyond.

What is Dominic Smith’s trade value like now with the hot spring and the success coming off the bench? You can’t trade your best bench bat midseason, but maybe next offseason, could the Mets look to deal him?
-- Steve P.

Over the winter, Dominic Smith’s trade value was quite low. That’s not going to change much over 12 good plate appearances, but you’re right to point out that Alonso’s success leaves the Mets without much playing time for Smith. While I don’t see a trade happening in the coming weeks, I’m curious to see if the Mets revisit their Smith-to-the-outfield experiment. They appeared to kill it for good this spring, but circumstances have changed since then.

Michael Conforto has always been a natural left fielder and Nimmo came to the big leagues in right. Why has Callaway been flipping them?
-- @ydhells_15

Two reasons. One, Michael Conforto has the stronger arm, which traditionally plays better in right field for those long throws to third base. Two, when Jed Lowrie is healthy, McNeil will theoretically be a full-time outfielder. That means Nimmo will play most days in center, and the Mets are more comfortable with McNeil in left than right. (Same goes, eventually, for Yoenis Céspedes.)

Is there any chance the Mets call a spade a spade and turn Wheeler into a reliever? He has the stuff and an electric arm, but he clearly doesn’t have the mental makeup to be a consistent starter. I feel that he’d thrive as a late-inning reliever. Let him let it rip for three batters.
-- @BaseballFollow6

At this point, no, there’s basically no chance of that happening. While it’s something the Mets discussed earlier in Zack Wheeler’s career, he proved last year he can be an elite starter when he puts it all together. More than that, New York simply doesn’t have the personnel necessary to swing a deal like that. Taking anyone out of the rotation right now would leave the Mets’ depth chart perilously thin.

Have patience with Wheeler. He may not replicate his second half of 2018, but he has the ability to be a strong middle-of-the-rotation starter once he hits his stride.

Why has Callaway not used Luis Avilan as a lefty specialist thus far? He’s had him face mostly righties and Avilan has struggled.
-- Rob

Because of Luis Avilán's signature pitch. It’s the changeup that allowed him to spike his strikeout rate when he began throwing it nearly half the time in 2016, helping him develop into a valuable reliever. Because the changeup breaks away from right-handed batters, it allows Avilan, theoretically, to neutralize them better than a typical lefty would.

Now, that hasn’t always been the case in Avilan’s career; so far this year, righties are crushing Avilan to the tune of a 1.636 OPS. It’s a small sample, but if it grows bigger, Callaway will have to consider limiting Avilan’s exposure to righties.