Four of MLBPipeline's Top 100 Prospects got called to the big leagues this week: Cardinals right-hander Jack Flaherty (No. 33) on Tuesday, Rays third baseman Christian Arroyo (No. 80) on Wednesday, Braves left-hander Max Fried (No. 81) on Thursday and Pirates outfielder Austin Meadows (No. 42) on Friday.
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Arroyo, Fried and Meadows all figure to have brief stays in the Majors as they cover for minor injuries to Matt Duffy, Mike Soroka and Starling Marte, respectively. Flaherty is clearly the best fantasy option for 2018, because his combination of stuff and polish have him poised to contribute immediately. He's filling in for Adam Wainwright, who's already making his third trip to the disabled list this season, and Flaherty has the opportunity to stick in St. Louis' rotation for a while.
Below are our updated rankings of the top 10 fantasy prospects presently in the Minors. As always, they're based solely on expected 2018 fantasy production in the big leagues, while our Top 100 reflects long-term value in all phases of the game.
1. Vladimir Guerrero Jr., 3B, Blue Jays (Previous rank: 6)
He's just 19 and has yet to play above Double-A, but he's absolutely annihilating the Eastern League and I'll boldly predict here that the second coming of Jose Cabrera could hit .270/.350/.450 with 12-15 homers if Toronto installed him in its lineup for the rest of the season.

2. Ryan McMahon, 1B, Rockies (Previous rank: 7)
Ian Desmond looks cooked at age 32 and it's unclear if he can do anything better than McMahon, who's getting his stroke back in Triple-A after rotting on Colorado's bench for the first month.
3. Nick Senzel, 3B, Reds (Previous rank: 1)
Senzel hasn't played since May 3 while dealing with vertigo -- which also bothered him at the end of last season -- but should return to game action in the next week or so. A tremendous pure hitter with all-around tools, he'll be ready to contribute when healthy.
4. Michael Kopech, RHP, White Sox (Previous rank: 2)
After displaying improved control in his first five starts, Kopech has battled the strike zone in his last two. Nevertheless, Chicago's rotation is a mess and his stuff rivals any prospect's anywhere in the Minors.

5. Eloy Jimenez, OF, White Sox (Previous rank: 4)
Jimenez has pounded Double-A pitching since returning from a pectoral strain, and none of Chicago's outfielders has been productive.
6. Alex Reyes, RHP, Cardinals (Previous rank: unranked)
Coming back from Tommy John surgery, Reyes struck out 12 in five innings and registered 100 mph with his fastball in a Monday rehab start in low Class A. He could bolster St. Louis' injury-riddled rotation or emerge as its closer by season's end.

MILB Video - Title: Reyes fans 12 - Url: http://www.milb.com/r/video?content_id=2044566183

7. Willie Calhoun, OF, Rangers (Previous rank: 5)
Calhoun's bat is waking up after a slow start, and Texas' best lineup would feature him in left field and Joey Gallo at first base on a regular basis.
8. Willy Adames, SS, Rays (Previous rank: 9)
He's significantly better offensively and at least as good defensively as Tampa Bay's regular middle infielders, Joey Wendle and Adeiny Hechavarria, so there's no reason to keep Adames in Triple-A for the second straight year.
9. Austin Riley, 3B, Braves (Previous rank: 10)
Riley continues to rake following a promotion to Triple-A in early July and Atlanta is playing to win, so he could get the call if Ryan Flaherty falters.

10. Juan Soto, OF, Nationals (Previous rank: unranked)
Soto entered Friday leading the Minors in homers (14) and ranking second in OPS (1.217) and already has earned two promotions. An elite hitting prospect, he could jump from Double-A to bolster a Washington outfield getting little out of guys not named Bryce Harper.
Dropped out: Jack Flaherty, RHP, Cardinals (Previous rank: 3); Tyler O'Neill, OF, Cardinals (Previous rank: 8).