What on earth is wrong with Paul Goldschmidt?

Coming into the season, the Arizona Diamondbacks' perennial MVP candidate had an average draft position (ADP) of 7.5 and was selected in the first round of virtually every season-long fantasy draft in the world. It was pretty easy to understand why, too. Since becoming an everyday player in 2012, he had put together three seasons of at least 30 homers, had three seasons of 100-plus RBIs, four seasons of 100 or more runs, and had never had a wOBA below .363. Not only that, he stole 117 bases in his career coming into the season, a high number for a first baseman.

But so far this year, Goldschmidt has simply been brutal. He has a slash line of .210/.339/.378. He's striking out 31.0% of the time with just 5 home runs and appears completely lost at the plate. This trend started last September, when he hit .171/.250/.305 with a .555 OPS and a wOBA of .240. He carried that into the start of this year as he began 2018 batting .118/.333/.206 in his first 10 games (45 plate appearances). He then put up a slash line of .385/.467/.769 in the 14 games that followed (60 plate appearances), but since April 27th, he has slumped again, hitting .105/.227/.123 in 66 plate appearances.

What's the problem? Velocity, apparently.

That's a worrisome note for Goldschmidt owners, as just about every pitcher in Major League Baseball, especially relievers, throws hard. Velocity is everywhere, and if a star player has lost his ability to hit pitches that come at a high velocity, production is going to drop dramatically.

Goldschmidt is still just 30 years old, so age regression shouldn't have kicked in already. But for fantasy owners who spent a high first-round pick on him, what do you do now? It's probably worth holding onto him in the immediate future to see if he figures things out, but if you can find someone who is willing to pay that first-round premium price to trade for Goldy now, it might be the right time to move him.

Here are the rest of the week's buy/sell options for Week 7.

Buy Odubel Herrera

Congratulations to you if you have owned Philadelphia Phillies outfielder Odubel Herrera from the start of the season. You've been able to ride his 41-game on-base streak (through Sunday), his league-leading .360 batting average (tied with Mookie Betts), his .430 on-base percentage (seventh-best in MLB), his wOBA of .426 (also seventh-best) and his wRC+ of 173 (tied for fifth-best).

Herrera has also provided more slugging prowess this year, up to a career high slugging percentage of .561. Last year's .452 slugging percentage was his previous high. His 6 home runs are almost halfway to his home run total from last year (14), making him a more well-rounded hitter.

But his plate discipline is the reason you can believe in this incredible start.

Herrera has increased his walk rate from 5.5% last year -- and a career mark of 7.2% -- to 10.1% this season. He's also seen his strikeout rate drop from 22.4% last year -- and a career average of 21.6% -- to 15.2%. He is swinging at far fewer pitches outside the strike zone (from 41.3% last year to 32.8% in 2018) and is making more contact inside the strike zone (87.0%, up from 84.4% last season).

Herrera is a player to target in any trade, provided you can find an owner willing to part with him.

Sell Billy Hamilton

Cincinnati Reds center-fielder Billy Hamilton came into the season with an ADP of 71, mainly because of his ability to steal bases. Up until Sunday, he hadn't been doing that too much.

Hamilton went into Sunday's game against the Los Angeles Dodgers with just 5 steals, a criminally-low number for a player who has stolen at least 56 bags each of the last four seasons, and offers nothing else otherwise. However, he did steal three bases against L.A. on Sunday, giving fantasy owners some level of reprieve.

While it's likely he'll steal more than he has already, it's tough riding a slash line of .215/.317/.322 with 7 extra-base hits in 139 plate appearances. And while he is walking more this year (12.9%, up from 7.0% last season), his strikeouts are way up, too (21.8% to 28.8%).

Use his three-steal game on Sunday to find a taker for a one-outcome player who hasn't given you much of that one outcome so far in 2018.

Buy Freddy Peralta

One should normally take a wait-and-see approach on a pitcher who has just made his Major League debut, but in this case, it's OK to buy some stock in Milwaukee Brewers starter Freddy Peralta.

Against a struggling Colorado Rockies lineup, Peralta whiffed those 13 batters almost exclusively with his fastball, which averaged only 91.4 miles per hour. He threw it almost 92% of the time against Colorado on Sunday, and yet, he got 19 swings and misses on the pitch. But Peralta has been a high-strikeout guy in the minors, so this isn't out of character for him.

In seven Triple-A starts this campaign, he struck out 11.94 batters per nine, and in 11 Double-A starts last year, he whiffed 12.86 per nine. He's traditionally had some issues with walks, but Sunday's performance and his minor league track record are enough to encourage fantasy owners to buy-in on Peralta.

Sell Dylan Bundy

Baltimore Orioles starter Dylan Bundy is too much of enigma to make any fantasy baseball owner feel good.

In his first five starts of the season, Bundy had a 1.42 ERA, 1.98 FIP, and 3.28 xFIP. He had struck out 11.37 batters per nine but hadn't lasted less than 5.2 inning in any start.

Then on Tuesday of last week, Bundy turned in what may go down as the worst start by any MLB pitcher this season, when he gave up seven earned runs and four home runs to the Kansas City Royals, lasting just 7 batters into the game without recording an out. In the two starts prior to that, he had given up five runs and seven runs, failing to make it out of the fifth inning in either start.

Then, on Sunday, "good" Bundy returned, with seven innings of two-hit, shutout baseball against the Tampa Bay Rays in which he struck out seven and walked four.

Somewhere inside Dylan Bundy lies a very good pitcher, but that very good pitcher hibernates for stretches. Sell him now after one of his good starts and save yourself the indigestion.

Hold Miles Mikolas

There are a lot of very good Major League pitchers in baseball right now, but there is one category in which one of the least-talked about hurlers in the game, St. Louis Cardinals right-hander Miles Mikolas, is owning the rest of the league.

Among 92 qualified starters, Mikolas leads the bigs in strikeout-to-walk ratio at 11.67, far and away better than the next-closest pitcher, Zack Greinke, who sits at 8.83. Mikolas is whiffing only 6.75 batters per nine right now, but he isn't walking anyone at 0.58 free passes per nine, the best mark in baseball.

Mikolas, who had been playing in Japan the last few seasons, has been a godsend for St. Louis this year, with a 2.51 ERA, 3.58 FIP, 3.10 xFIP in seven starts. He's getting grounders at a 53.5% clip and is looking like an All-Star so far in 2018. I'm not sold that someone with that lack of strikeouts is worth buying, but if you own him, hang onto him for a bit. This may be for real.

Sell Matt Adams

First baseman Matt Adams has been an absolute savior for the Washington Nationals so far in 2018.

Taking much of the playing time from a struggling Ryan Zimmerman, Adams has been worth every penny of the $4 million the Nats spent on him this winter. In 35 games (113 plate appearances), he's batting .274/.389/.642 with 10 bombs, 25 RBIs and 18 runs scored. Not bad for a player with an ADP of 461 coming into 2018. Compare that to Eric Hosmer -- who the San Diego Padres gave eight years and $144 million and came into the season with an ADP of 82 -- as Hosmer is batting .262/.363/.462 with 5 homers, 13 RBIs and 19 runs.

Most important for Adams is that he's holding his own against southpaws, with a .250/.333/.500 slash line against them in 18 plate appearances. With Zimmerman hitting the disabled list, Adams is going to get more looks against lefties, but it now appears Mark Reynolds (who hit two homers on Sunday) is going to eat into that a bit.

It's also true Adams is going to cool off a bit, so you can cash in on that free-agent flier you got and see what you can get for him.

Buy Nick Markakis

Atlanta Braves outfielder Nick Markakis has had a pretty good career, most of it spent with the Baltimore Orioles during his prime. So it's interesting that, at 34 years old, he's never made an All-Star team. That's likely to change here in 2018.

After going largely undrafted in fantasy this preseason, Markakis' .344 batting average is 2nd in the National League behind Herrera, his .416 on-base percentage is 5th, and perhaps most surprisingly, his slugging percentage of .541 is 13th. He's hit seven dingers this year, one short of last year's total of eight. The most homers he's ever hit was 23, and that was done in his second season, 2007, when he hit 23.

Markakis has increased his isolated power (ISO) from .110 last season to .197, all while slightly increasing his walk rate (from 10.1% last year to 11.2%), and decreasing his strikeout rate (9.0%, down from 16.4% in 2017). As a left-handed hitter, he's destroying lefties, batting .377/.431/.585 in the split with a better OPS (1.016) against lefties than against right-handers (.928 OPS).

This is for real, and if you haven't gotten in on the Markakis bandwagon, do so now.

Buy Edwin Encarnacion

Like many members of the Cleveland Indians' lineup, Edwin Encarnacion got off to a slow start. But given his track record, no one was really all that worried that his early-season slump would last.

Well, it's mid-May and Encarnacion -- who has hit at least 36 homers every season since 2013 and has crossed the 40-homer plateau twice -- is batting .204/.280/.408 with a wOBA of .298 and a wRC+ of 82. Yes, he has 9 homers this season, including a 3-homer game earlier this month. But in 158 plate appearances, he has just two doubles. Two!

Even more troubling are the peripherals. Encarnacion's walk rate has fallen from 15.5% last year to 7.6% this year, and his strikeout rate has skyrocketed from 19.9% in 2017 to 27.8% this year. He's swinging at more pitches out of the zone (a career-high 29.8%) and is seeing a first-pitch strike 63.3% of the time, way up from last year's 52.6%.

However, it's important to note that Encarnacion has traditionally been a slow starter, with a career .742 OPS in April and .821 OPS in May. His OPS for June is .948, it's .884 for July, it's .879 in August and is .847 in September.

Buy now, because he's probably going to heat up soon.

Buy Tyler Clippard

Fantasy owners are always on the lookout for new closers, and it appears as if Tyler Clippard is going to be the new closer for the Toronto Blue Jays. The incumbent, Roberto Osuna, was placed on the seven-day administrative leave list after accusations he assaulted a woman.

It's unclear how the Jays will respond (he was due to come off the list Monday, and no decision had been made as of this writing), but if Osuna is out for a while, it appears Clippard is the reliever to own. He's been one of Toronto's best bullpen arms this season, sporting a 1.23 ERA and striking out 9.82 batters per nine in 22 innings of work.

He does have a high walks per nine of 4.09, but that's not a whole lot different than his career numbers. And while his 100% strand rate certainly won't hold up, he is doing a better job of keeping the ball in the yard this year, giving up 1.23 dingers per nine, lower than each of the last two seasons.

He's not a stud closer, but he's worth buying to pile up some saves if Osuna is going to miss significant time.