Champ or Chump - Fernando Tatis Jr. and Yoan Moncada

It can be incredibly easy to overreact to your team's performance thus far, but remember that it is still very early. You shouldn't even be thinking about dropping big names like Aaron Nola or Mookie Betts, nor should you count on Daniel Vogelbach or Jay Bruce continuing their home run binge.

That said, you don't want to be too slow to react to trends either. Fernando Tatis Jr. and Yoan Moncada have both dramatically exceeded preseason expectations thus far, and they have underlying peripherals that suggest they could remain good (if not quite as good) all season long.

Keep in mind, our Champ / Chump conclusions are based on whether we think a player will outperform their expectations. For example, a pitcher we view as "Tier 2" can be a Champ if they're seen as a Tier 3 pitcher, or they could be a Chump if they're perceived as a Tier 1 pitcher. All ownership rates are from Yahoo! leagues unless otherwise noted. Let's take a closer look at Tatis and Moncada, shall we?

Fernando Tatis Jr. (SS, SD)

79% Owned

This 20-year-old wunderkind is off to a scintillating start, slashing .281/.347/.578 with five homers and a steal in 72 PAs. The big knocks against him coming into the season were playing time and plate discipline. The Padres bucked the service time manipulation trend by breaking camp with the shortstop, leaving plate discipline as his only major question mark.

Tatis recorded 394 PAs at Double-A last season, walking at a reasonable rate (8.4 BB%) but striking out at an unacceptable 27.7% clip. He's been even worse at the big league level this year, recording a 30.6 K% against a 6.9 BB%. At first glance, you might suspect that Tatis is bound to come crashing down to Earth. However, his plate discipline peripherals suggest that Tatis might be okay.

Tatis is chasing 32.3% of the pitches he sees outside of the strike zone, just a smidgen more than the league at large (29.2% thus far). Similarly, his 11.9 SwStr% is only marginally higher than the league's mark of 11.1%. It would be one thing if Tatis was overly passive at the plate, but his 47.3 Swing% is higher than the league's 45.5% rate. There is some risk that his peripherals decline based on his MiLB history, but they've been fine so far. To date, his plate discipline should be slightly worse than league average, suggesting substantial room for his 30.6 K% to decrease.

Tatis's pop also looks at least partially sustainable. Statcast likes what it sees, as Tatis has above average airborne exit velocity (94.4 mph) and an excellent 16.3% rate of Brls/BBE. He's also pulling a healthy 26.3% of his flies, making it easier to lift the ball out of the park.

He probably won't maintain his 26.3% HR/FB all season long at PETCO Park, but his 45.2 FB% is high enough to produce a reasonable number of homers anyway if he can sustain it. Tatis's low 14.3 LD% suggests that some of his flies will become line drives moving forward, and he had an average 35.1% fly ball rate at Double-A last year. However, his 43 FB% at Single-A in 2017 gives Tatis some track record of strong FB% rates.

Tatis also has speed to burn, but his stolen base success rates haven't been stellar on the farm. He went 15-for-18 on SB attempts in 2016, but a volume spike in 2017 led to a success rate of just 68% (32-for-47). He got back up to 76% last year, but it came at the expense of attempts (16-for-21). He's 1-for-2 so far at the MLB level, so he might not run as much as you think.

The only other red flag is that the Padres have hit Tatis at the bottom of the lineup despite his hot start. He'll disappoint in R+RBI if he can't earn a promotion, but his stats to date suggest that this is a hot start worth believing in. It isn't advisable to pay a premium in trade for Tatis in redraft leagues, as there's always risk in rostering a 20-year-old. However, his peripherals don't support moving him for pennies on the dollar either. This kid is big league ready.

Verdict: Champ (based on 79% ownership rate)

Yoan Moncada (2B/3B, CWS)

86% Owned

The 23-year-old Moncada is slashing .333/.371/.652 with five homers and a steal in his 70 PAs, a dramatic uptick from his .235/.315/.400 line with 17 HR and 12 SB a season ago. Moncada has always made outstanding contact (.346 career BABIP), but strikeouts have been a major bugaboo for him (33.4 K% last year). So far in 2019, he's only striking out 24.3% of the time. Has he solved his biggest problem?

Moncada appears to have discovered a workaround. He never really whiffed too often (12.4 SwStr% career) or chased too many bad pitches (24.3 O-Swing%), instead striking out because he was too passive at the plate (64.2 Z-Swing%). So far in 2019, Moncada is more aggressive on pitches in the zone (70.1 Z-Swing%). It's worth noting that he's also chasing more pitches outside of the zone (27.3% vs. 24.3% career), so Moncada hasn't improved his eye at all. He's just stepping up to the plate more willing to swing than he used to be.

The downside of that approach would be a loss of contact quality, but Moncada doesn't seem to be having an issue with that. His 98.4 mph average airborne exit velocity in 2019 is excellent, as is his 20.4% rate of Brls/BBE. Moncada had a 94.2 mph average airborne exit velocity and 9.6% Brls/BBE last season, and very few batters sustain his current marks over a full season. Thus, regression is likely, but the fact that his numbers are this good right now is all the evidence we need to conclude that a more aggressive Moncada can produce the same contact quality the more passive version did.

Everything else about Moncada is generally favorable. His 42.9 FB% (40.1% in 2018) suggests that he lifts the ball often enough to take advantage of Guaranteed Rate Field's cozy dimensions. He's pulling a lot more fly balls (28.6%) than he has over his career (18.1%). He doesn't care about the shift at all (.398 in 169 career PAs against it), and he has plus foot speed (28.8 ft./sec Statcast Sprint Speed last season). Heck, he's even moved to the second spot in Chicago's batting order for maximal counting stat opportunities.

The one remaining weakness in Moncada's game is his general inefficiency on the base paths. His 12 swipes last season came with six CS for a 66% success rate that just won't cut it at the MLB level. His .386 BABIP and 23.8% HR/FB are also likely to regress to some degree even if both are likely to land above the league average. If you decided to roll the dice on Moncada in your 2019 drafts, it looks like you just might get the breakout you have been hoping for.

Verdict: Champ (based on 86% ownership rate)

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