Last season brought us a star-studded group of rookies who now face the difficult task of building off that success.

Lewis Brinson of the Marlins and Scott Kingery of the Phillies are confronting a different sort of challenge. Both entered 2018 with high expectations and a wide-open chance to establish themselves as Major League contributors. Both struggled mightily, inviting questions about their long-term potential.

Brinson has been a top-30 prospect in MLB and the centerpiece of two different high-profile trades, going from Texas to Milwaukee in the 2016 Jonathan Lucroy deal, then from Milwaukee to Miami in last January’s Christian Yelich swap. Installed in center field last season, the 24-year-old batted just .199/.240/.338 with 11 home runs in 406 plate appearances while striking out 120 times against only 15 unintentional walks.

A second-round pick in 2015, Kingery enjoyed a big '17 in the Minors to raise his prospect stock dramatically. That helped prompt the Phillies to sign him to an extension before last Opening Day that could run through the '26 season if three team options are exercised. Kingery accrued nearly 500 plate appearances as Philly’s primary shortstop but managed only a .226/.267/.338 line with eight homers, 10 steals and 126 strikeouts.

There were 214 players who came to the plate at least 400 times last season. In terms of OPS+, a park-adjusted metric for which 100 is average, Kingery (61) and Brinson (62) ranked third and fourth lowest among that group.

There are still reasons to believe in both players, not just because of their tools, but also because there are a number of big-name players who struggled just as much in their rookie years before finding stardom. Before we get to them, let's take a look at where things stand with Brinson and Kingery.

Good and bad of Brinson, Kingery

Brinson has excellent wheels, with Statcast tracking him at an average sprint speed of 29.4 feet per second last year, which put him among the top 5 percent of MLB players. That helped him post solid numbers with the glove -- plus-3 in Defensive Runs Saved and plus-2 in Statcast’s Outs Above Average. He also showed an ability to square up the ball when he made contact, ranking above average in hard-hit rate (38.7 percent) and barrel rate (8.7 percent). Brinson was one of only 21 hitters to smack multiple homers with an exit velocity of at least 113 mph.

On the other hand, Brinson showed a tendency to chase out of the strike zone, missed on about 34 percent of his swings and struck out in nearly 30 percent of his plate appearances -- both among the highest rates in MLB. And while he hit the ball fairly hard, Brinson also put it on the ground 53 percent of the time.

Kingery tied Brinson in sprint speed and added value on the bases. Unlike Brinson, he showed aptitude for getting the ball in the air, with nearly 39 percent of his batted balls coming in the launch angle “sweet spot” that produces the vast majority of extra-base hits. Kingery ranked among the top 10 percent of MLB hitters in that category, putting him right near Anthony Rendon, Mookie Betts and Michael Brantley.

But like Brinson, Kingery chased too many pitches, whiffed frequently and piled up strikeouts while drawing few walks. His 31.1 percent hard-hit rate was below the MLB average, making it more difficult to take advantage of those line drives and fly balls.

It’s clear that both players must make some serious adjustments going forward.

Perhaps Brinson is showing signs of that this spring, with five home runs in his first 16 Grapefruit League at-bats through Monday. He should continue to get every opportunity to prove himself in Miami. The road to playing time might be a bit tougher for Kingery, although he could push Maikel Franco at third base while backing up around the infield.

Reasons for hope

There is precedent for a turnaround, even if history suggests this will be an uphill battle.

In the 20 seasons from 1991-2010, 84 no-longer-active rookies posted an OPS+ of 70 or lower in at least 200 plate appearances, at age 25 or younger. Of those light-hitting rookies:

-- 25 (30 percent) got 2,500 more plate appearances over the rest of their careers.
-- 16 (19 percent) produced at least 10 WAR over the rest of their careers.
-- 8 (10 percent) posted an OPS+ of at least 100 over the rest of their careers.

For some context, here are the seven players who fit into all three groups, in order of career WAR (per Baseball Reference): Aramis Ramirez, Jhonny Peralta, Brian Roberts, Paul Konerko, Rich Aurilia, Doug Mientkiewicz, Todd Hundley.

And here are five recent examples who are separate from the 84-player sample noted above who should give Brinson and Kingery some inspiration:

Jackie Bradley Jr.
Rookie season (2014): 423 PA, 49 OPS+

Bradley first came to the Majors with significant prospect hype in '13 and struggled (107 PA, 68 OPS+), though he retained rookie eligibility into '14. Then things got even more dire, as Bradley struck out 121 times, hit just one homer and was demoted to Triple-A. His bat has offered highs and lows since -- including a strong second half in '18 -- but over four years Bradley has been above average at the plate (103 OPS+) to go with his stellar defense in center.

Javier Baez
Rookie season (2014): 229 PA, 52 OPS+

A consensus top-10 prospect entering the '14 season, Baez flopped, thanks in large part to an extremely raw approach. Then again, he was only 21 at the time -- a few years younger than Brinson and Kingery. While Baez is still a hacker, that didn’t stop him from posting a 126 OPS+ last year. Combined with his baserunning and excellent infield defense, that netted Baez 6.3 WAR and made him the NL MVP runner-up.

Aaron Hicks
Rookie season (2013): 313 PA, 63 OPS+

As recently as '16, it still seemed like a then 26-year-old Hicks might never make good on his prospect pedigree. But the fleet-footed center fielder has turned things around to generate a 123 OPS+ with 42 homers and 21 steals since, his all-around game making him one of the top-30 position players in WAR (8.6) over that period. The Yankees rewarded him last month with a seven-year contract extension.

Marwin Gonzalez
Rookie season (2012): 219 PA, 65 OPS+

It didn’t get any better for Gonzalez the next year (222 PA, 58 OPS+), but in the five seasons since, the switch-hitter has been well above average with the bat (111 OPS+), contributing to a championship Astros club. Defensive versatility has been a key to success for the recent Twins acquisition, something Kingery may need to emulate in the near future.

Brian Dozier
Rookie season (2012): 340 PA, 67 OPS+

Dozier hit a grand total of 16 homers in more than 1,600 Minor League plate appearances and just six in his first taste of the Majors. It didn’t take him long to tap into his power, though. Since '13, Dozier’s 166 big flies lead all MLB second basemen by a wide margin, while his 23.2 WAR ranks fourth.