Are these 5 early-season hitting breakouts for real?

The Pittsburgh Pirates and Baltimore Orioles aren't the only ones producing shocking results this season. Some unexpected - and in some cases, unfamiliar - individual player names sit atop a number of Major League Baseball leaderboards.

Which April breakouts among position players appear to have staying power? And which ones look more likely to fade away? Let's assess five of them.

James Outman, Dodgers

The Los Angeles Dodgers did little to upgrade their roster externally this offseason, likely saving their future spending flexibility to court Shohei Ohtani this winter. They moved on from Cody Bellinger, who played 1,223 innings in center field last year, and entrusted the position to internal candidates like James Outman and Trayce Thompson.

So far, it's working out, as Outman seized the job and is moving up the batting order. The left-handed hitter is even starting against left-handed pitching. He entered play Friday fifth in the majors in position-player WAR.

Outman always had tools. He was three home runs short of back-to-back 20-20 seasons in the minors in 2018 and 2019. He launched 32 home runs a year ago across three levels. He generates plenty of loft and bat speed with a sweet left-handed stroke, and he's an excellent all-around athlete with 90th-percentile sprint speed and arm strength.

The questions about Outman concerned the swing and miss in his game. His strikeout rate was elevated in the minor leagues and sits at 31.6% in 2023. While that's well above the MLB average, it remains in line with his minor-league track record. Swing rates and whiff rates usually stabilize early in the season, so this could be who Outman is, and that's still a good player. When he makes contact, it's usually loud.

While he's not likely to finish fifth in the majors in WAR, he may be shaping up as an annual 2-3 WAR player who can impact a game in multiple ways. Perhaps the Dodgers were not aggressive enough this offseason, but Outman looks to be a quality regular - or at least a quality fit on the strong side of a platoon.

Brent Rooker, Athletics

The Oakland A's are so depleted that they might struggle to win 50 games this season. While their pitching is the worst in the majors - and historically poor to open the season - their offensive production is only mildly disappointing. They're 17th in wRC+ (98), just 2% below average MLB offensive efficiency. And that's in part because of a surprising first month from Rooker, who's hit more home runs (eight) than Aaron Judge (six) to date.

He even homered off Ohtani this week.

Rooker comes with prospect pedigree. He was a star in college at Mississippi State, where he won the triple crown in the Southeastern Conference in 2017, and was drafted 35th overall that year by the Minnesota Twins. But he's never had an extended chance in the majors. He was traded twice in 2022 and Oakland grabbed him off waivers in November.

With the lowly Athletics, he should play nearly every day this year. So far, so good. His Statcast page is a sea of red, which means he's hitting the ball nearly as hard as Judge, too.

For players with 70 or more plate appearances, he is first in the majors this season in wRC+ (232). He's in the top 4% of expected slugging and walk rate. Those numbers look very real. The thing to watch is whether he can keep his strikeout rate below 20% (it's 16.9% through Friday's games).

Since he's never had a real run in MLB, it remains to be seen how pitchers adjust to him. He won't finish the year with an OPS above 1.000, but he looks like he can be an above-average hitter and fill an outfield corner role for the Athletics - or another team as a trade target.

Brandon Marsh, Phillies

If you had the long-bearded Philadelphia Phillies center fielder leading the majors in OPS through April 24, congratulations. Also, you were certainly alone.

There's reason to believe that Marsh didn't suddenly become a star-level outfielder. He entered play Saturday with a .469 batting average on balls in play, more than 150 points above the league rate.

Marsh is still striking out at a high 28% clip and his average launch angle remains in line with his career levels. He's also still pounding balls into the ground more often than he's lining them into the air. Expect regression.

Jarred Kelenic, Mariners

We're often reminded that prospect development isn't linear, but Kelenic is taking that maxim to an extreme this spring.

After struggling mightily in his first two years in the majors, each of which included sub-.200 batting averages and demotions to the minors, Kelenic is performing more like the can't-miss prospect the Seattle Mariners acquired in the Edwin Diaz trade during the 2018-19 offseason.

His raw tools have never been in doubt, and now they're translating to results more often. Kelenic is making better contact and inflicting more damage when he does.

Perhaps most encouraging is that after below-average MLB performance against every pitch type last year, he's above-average against everything except changeups this season.

He might not be an MVP candidate just yet, but it looks like the Mariners do have another core piece alongside Julio Rodriguez.

Nico Hoerner, Cubs

No player is taking advantage of baseball's new rules quite like the Chicago Cubs second baseman.

Hoerner never stole more than 20 bases in a single season dating back to his time at Stanford, and he's already stolen 10 this year. He's not going to steal 65 … at least, probably not. But given his career success rate of 38-for-47, he should set a career high this season and could certainly push for 30-plus.

The bigger question is whether he can maintain his 6.8% strikeout rate. That's a little more than half of his career mark and the second-lowest in the majors, trailing only contact-hitting savant Luis Arraez of the Marlins.

We're betting that this is largely real and Hoerner is the kind of high-contact, speed-plus-instinct player the new rules were designed to boost. The Cubs' lineup looks legit, and having Hoerner at the top helps.

Travis Sawchik is theScore's senior baseball writer.