Watch Now: Who are the buyers and sellers in the NL? ( 1:36 )

Fantasy Baseball: Add Rondon, Rodon on waivers | Six SPs outside the Circle of Trust

So you're wondering about that hot hitter, huh? Will he be able to keep it up? Should you add him or sell high — whichever applies?

You probably already know the answer. In the immortal words of Dennis Green, the Bears are who we thought they were.

But of course, sometimes players genuinely do improve, and the sooner you realize it, the more likely you'll be able to capitalize.

These four? I'm ready to crown them.

Jose Martinez CHC • 1B • 53 2018 season BA .327 HR 10 OPS .928 BB 26 K 34 View Profile

Jose Martinez's ownership percentage, at least in CBS leagues, hasn't dipped below 81 at any point this season, but there were times when he looked like nothing more than also-ran at two especially deep positions. In fact, just last week on the Fantasy Baseball Today podcast, I suggested that power may not be his game and 20 homers might be the upper limit. He has homered five times in five game since.

So now it's a 25-homer pace, and you know what? It's not so far-fetched. As hard as he hits the ball, it stands to reason he'd have a home run-to-fly ball rate about on the level of Paul Goldschmidt (just like he did as a part-timer last year), allowing him to exceed 20 despite having more of a line-drive stroke. It's those line drives, combined with the hard hitting combined, with the all-fields approach combined with a low strikeout rate that make Martinez a certifiable batting title contender, which altogether gives him top-10 potential at first base.

These were possibilities I was willing to entertain before the start of the season, when I listed him as one of my sleepers, and I'm reaffirming that stance today.

Eduardo Escobar ARI • 3B • 5 2018 season BA .288 HR 12 2B 26 OPS .908 AB 229 View Profile

Flying under the radar among who-could-have-seen-this-coming-type developments is the fact Eduardo Escobar is on pace for more than 100 extra-base hits — specifically, 31 homers, three triples and 68 doubles. Jose Ramirez is on pace for 99. Mike Trout, at least heading into Monday night's game, was on pace for 94.

It's stupefying for a 29-year-old utility player, but also not entirely out of left field when you consider the way he finished last season. It was then that he joined the fly-ball revolution, getting his rate up over 40 percent for the first time. But the biggest leap came in September, when he homered nine times in 114 at-bats. It would have been easy to dismiss as a fluke if not for this year's follow-up. The fly-ball rate is even higher, so this power surge hasn't needed to rely on a bloated home run-to-fly ball rate, and now the line-drive rate is also up to a Martinez-like 26.1 percent.

In that context, Escobar's .329 BABIP doesn't seem the least bit crazy, especially considering he also has a career-high hard-contact. In fact, the only red flag here is that he's Eduardo Escobar, who shouldn't be capable of these things. But for the chance at this kind of production from a shortstop, that's not enough of a red flag for me.

Brandon Nimmo NYM • LF • 9 2018 season BA .271 OBP .413 HR 8 SB 6 OPS .969 View Profile

About the one remaining hangup for Brandon Nimmo — who's still available in about a quarter of CBS leagues, by the way — was that he didn't have a clear path to everyday at-bats. But manager Mickey Callaway seems to recognize that the 25-year-old has been the Mets' best hitter this year, recently telling Joel Sherman of the New York Post that he'll keep Nimmo in the lineup even after Yoenis Cespedes returns.

So problem solved. There shouldn't be any doubts by now that Nimmo is an on-base machine. Even as a rookie, he reached base at a .379 clip in 215 plate appearances. It was his game coming up through the minors, too, where he compiled a .388 mark in parts of eight seasons. The difference this year is he's hitting for the power many scouts thought he'd develop eventually — and in a way that's believable, with his fly-ball rate rising from 32.8 percent to 45.9 percent.

If he hit lefties a little better, I'd have no reservations calling Nimmo must-own, but even with his struggles against them, he's the No. 7 outfielder in points leagues since becoming an everyday player May 9.

Max Muncy LAD • 3B • 13 2018 season BA .272 OBP .395 HR 12 OPS 1.011 AB 125 View Profile

You know who's one spot ahead of Nimmo during that same period of time? That's right: Max Muncy. In fact, the only five outfielders to outscore Muncy and Nimmo since May 9 — which I realize is an arbitrary starting point for most of them, but hey, we're already down this path — are Andrew Benintendi, J.D. Martinez, Mike Trout and Michael Brantley. Fine company, in other words.

Like Nimmo, Muncy's numbers are bolstered by a high walk rate that, like Nimmo, was present throughout his time in the minors, where he reached base at a .382 clip across seven seasons. The power wasn't as regular, but he did hit 25 homers back in 2013.

And look, he won't keep homering every 10 at-bats. His present home run-to-fly ball rate was bettered by only four hitters last year, and three of them were Aaron Judge, Giancarlo Stanton and Joey Gallo. We're talking the sort of other-worldly power that you couldn't reasonably project for anyone. But at the same time, Muncy's fly-ball, hard-contact and pull rates would have all ranked in the top 10 last year. By every way we know how to measure home run potential, he measures up.

Plus, his BABIP's a little on the low side, so it's not like his batting average is certain to tank once the home run pace slows. Even if he's only like a .250 hitter, between the 30-homer power and high on-base rate, the Dodgers will keep finding at-bats for him at one of three positions, giving him a chance to be the player we thought we were drafting Matt Carpenter to be.