I frequently say that the minors are the only place to find impact players on the waiver wire this time of year. That's not entirely true, as a gifted player another owner gave up on may become available to you if he starts looking better.

Luke Weaver is a perfect example of the first group: a minor leaguer with a resume suggesting that he will be able to contribute immediately at the big league level. Byron Buxton personifies the latter group as a player with all of the raw talent in the world but little production until the last month or so. Let's take a closer look at these two young players, shall we?

Ownership rates provided are from Yahoo! leagues.

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The Fantasy Jury is Out

Luke Weaver (SP, STL) 52% Owned

Weaver has been excellent so far this year, compiling a 2.48 ERA (3.11 xFIP) in 29 IP. His surface stats were dreadful in a brief taste of the majors last season (5.70 ERA in 36 1/3 IP), but his peripherals suggest that he was actually a solid performer (3.34 xFIP). Can Weaver be trusted in the season's final stretch?

He can if his minor league history is any indication. Weaver dominated at the Double-A level last year, posting a 1.40 ERA (2.58 xFIP) in 77 IP. He struck out an impressive 28.6% of the men who faced him while walking just 3.3% of them, producing a K%-BB% of 25.3%. The sample was short, but his BABIP against (.289) was normal while his favorable HR/FB (5%) is supported by his previous minor league work. Weaver earned his cup of coffee last season.

He saw Triple-A for the first time this season, posting an ERA of 2.55 (3.97 xFIP) over 77 2/3 IP. His K% (24.9%) and BB% (6.2%) weren't quite as dominant as they were at the lower level, but the resulting 18.7% K%-BB% was still strong. His BABIP (.291) was well within the normal range, and he again suppressed the number of homers he allowed (3.7% HR/FB).

This strikeout ability has translated very well to the major leagues. His MLB K% last season was an impressive 27%, a number he has surpassed so far this year with a 30.3% mark. Young guns frequently struggle with control as they are striking out the world, but Weaver really hasn't (7.2% BB% in 2016, 7.6% this year). In terms of stuff, Weaver uses a solid fastball (career 57.6% Zone%, 7.6% SwStr%) to set up a strong change (18.1% SwStr%, 43.3% chase, 32.6% Zone%). He occasionally features a curve (4% SwStr%, 25% chase, 28.7% Zone%) and cutter (11.6% SwStr%, 18.2% chase, 36.2% Zone%), but neither has developed into a viable third offering yet.

Weaver's poor start in the majors was caused by an inflated BABIP (.386) and HR/FB (21.2%), but he did not struggle with either on the farm. In fact, his career FB% at the MLB level (32.6%) is much lower than it was in the Double-A (40.2%) or Triple-A (39.5%) samples mentioned above. Limiting fly balls is the best way to prevent home runs in this environment, and Weaver has been able to do it so far. This season's .314 BABIP and 13% HR/FB are likely sustainable for the rest of the year.

The Cardinals should also be able to support their young starter capably. The team has a collective wRC+ of 101, suggesting that Weaver will get at least an average amount of run support to help compile Ws. Their defense has also been strong with 23 Defensive Runs Saved as a unit. Jedd Gyorko has been excellent at 3B (16 DRS), while the team can field three above average defensive outfielders if they want to (Tommy Pham eight DRS, Stephen Piscotty six, and Randal Grichuk five.) First baseman Matt Carpenter (four) and catcher Yadier Molina (five) also rate as quality defenders.

The Cards banished Aledmys Diaz and his -10 DRS to the minors, eliminating one of the club's worst defenders. Dexter Fowler (-12 DRS) and outfielder Jose Martinez (-6) have been pretty bad, but Weaver can count on above average glovework from his teammates as a whole. That gives us an arm who figures to post a well above average K% without walking too many guys on a reasonable club. This profile needs to be owned in a lot more leagues.

Verdict: Champ

Byron Buxton (OF, MIN) 74% Owned

Buxton has all of the natural gifts you could hope for, but his .249/.310/.402 line with 13 HR and 24 SB has been more solid than spectacular so far. His season numbers are boosted by an incredible August (.327/.358/.634 with eight homers), without which he would clearly be a bust. Buxton teased us like this last September too (.287/.357/.653 with nine homers), so potential owners may be leery if they were fooled the first time.

While last September was obviously a fluke, it looks like Buxton is actually a little better now. He has traditionally struggled to make contact with the baseball, striking out an outrageous 35.6% of the time last season and a still unacceptable 28.4% of the time this season. The change is supported by SwStr% (15% last year, 12.8% this), so the slight improvement seems real. His hot September last season did nothing to address this contact issue, as he posted a 33.6% K% in his hot month. His K% in August this year is down to 22.3%, his second consecutive month with a reasonable figure (22.9% K% in July).

Buxton's wheels are also dependable, as he has only been caught stealing once in 25 attempts. It is a little concerning that he decided not to run too much last season (17 for 19 across Triple-A and MLB), leaving open the possibility that he runs only when he feels like it. Still, this is a guy with as many as 55 SB in a single campaign. His speed is a clear fantasy asset.

This does not mean that Buxton has become the All-Star he is capable of becoming. His contact quality is virtually unchanged from last year, as he is averaging 92.4 mph in the air this year against 92.7 mph last season. His rate of Brls/BBE is up slightly (5.3% to 6%), but this positive development is counterbalanced by a decrease in FB% (43.3% to 37.8%) and an increase in IFFB% (13.5% to 18.2%). He is pulling a few more flies (36.4% this season, 32.4% last) to produce a better HR/FB (14.8% vs. 13.5%), but this profile suggests 20 HR at best.

His .325 BABIP is right on his .322 career mark, but there is reason to believe that this may fall as well. Buxton historically gets a lot of value out of his ground balls by hitting them softly (77 mph average exit velocity this year, 78.6 last year) and using his legs to beat out a hit. He only pulled 61.7% of his grounders last year, so there was little reason to shift him. This season, however, he is pulling 71% of his grounders. He's still hitting .408 against the shift, but it could be hard to maintain his current .290 BABIP on ground balls if he keeps pulling them all.

Buxton's fly balls are worthless if they don't go over the fence (.040 BABIP this year, .082 career), a problem likely caused by all of the pop-ups he hits. His current 22.3% LD% is also higher than anything else in his track record, suggesting that he will hit fewer of them going forward. Line drives are the best batted balls for BABIP purposes, so losing a few of them will hurt.

The Twins have been hitting Buxton fifth lately, giving him adequate RBI opportunities at the expense of chances for runs scored. Plate discipline is one of the fastest things to stabilize, but it is still difficult to count on his positive developments in that department considering how terrible he looked for so long. He has the physical tools to be Billy Hamilton on the bases, but may not have the same drive to run as often. His power is middling at best, and his BABIP has plenty of room to decline. Roll the dice if he's available to you for free, but I wouldn't want to part with anything significant for him at this time. He's still a work in progress.

Verdict: Chump

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