The 2024 season saw a number of Major League Baseball stars break out in surprising fashion. Some came out of nowhere, while others were former top prospects no one expected much from once the initial hype wore off.
Let’s use some advanced metrics to examine five breakout stars from 2024 and look at whether their success is a mirage or can be maintained moving forward.
LF Jurickson Profar, Atlanta Braves
Profar exploded last season for the San Diego Padres, having the kind of season at 31 years old that many predicted when he was the consensus top prospect in baseball in his teens. The outfielder earned his first All-Star berth and a Silver Slugger award as he recorded career bests in batting average (.280), on-base percentage (.380), slugging percentage (.459), home runs (24), RBIs (85), walks (76) and runs (94). It was a brilliant season on a $1 million contract that he parlayed into a three-year, $42 million deal with the Atlanta Braves.
Profar had long owned one of the best eyes in the game with tremendous plate discipline, but something flipped last season that led to him driving the ball more. His average exit velocity jumped from 86.5 in 2023 to 91.1 in '24, moving from the ninth percentile to the 80th. As a result, his xSLG jumped from .349 to .444 and his xwOBA rose from .306 to .364. It's a simple equation—if you hit the ball harder, you're more likely to get on base and show more power. It's worth noting Profar's BABIP was also a career-high .302, which could mean some of his success was due to a bit of luck.
Profar's highest average exit velocity before his breakout campaign was 87.5 in 2022, so last year was a total outlier. The Braves believe he’ll maintain his refined approach and lower-half adjustments to his swing, according to . He'll be one to watch this season to see if he can back up the numbers he piled up in '24. He's certainly always been talented enough to produce this way.
SP Luis Gil, New York Yankees
Gil had just seven MLB starts under his belt heading into last year after spending most of 2022 and ’23 recovering from Tommy John surgery, so it would’ve been optimistic to project a full season’s worth of starts in the Yankees' rotation. But he went on to be named the American League Rookie of the Year, going 15–7 with a 3.50 ERA, a 1.19 WHIP and 171 strikeouts in 151 2/3 innings.
Gil's fastball velocity (96.6 mph) was sixth among starters with at least 150 innings pitched and had a 28.5% whiff rate, quite an effective mark for a heater. His hard slider is his best pitch (31.5% whiff rate), but his changeup isn’t too shabby, either, clocking in as one of the fastest in the majors at 91.6 mph. The downside to his stellar campaign was his 12.1% walk rate, which caused him to lead the majors with 77 free passes in a reflection of his command issues. Perhaps most concerning was an xFIP of 4.36, suggesting he got help from good fielding or luck to keep his ERA down. When you factor in an average exit velocity in the 35th percentile and an opposing chase rate in the 15th percentile, his future looks shakier than the surface numbers would suggest.
The Yankees are fortunate in that Gil is part of a rotation that includes Gerrit Cole, Max Fried and Carlos Rodón, taking some pressure off the 26-year-old. A lat strain suffered during spring training will likely keep him on the injured list until May, but once he recovers he's likely to pitch more like a middle- or back-end starter than an All-Star.
Duran emerged as a solid, speedy outfielder for the Boston Red Sox in 2023, but the former seventh-round pick exceeded all projections for him last season by ranking fifth in the majors with 8.7 WAR. Duran slashed .285/.342/.492 in his first full MLB campaign at age 27, leading the majors with 48 doubles and 14 triples to go along with 21 homers, 111 runs and a .834 OPS. He also made the most of his All-Star Game debut by launching the game-winning home run to earn the contest’s MVP honors and was eventually named a second team All-MLB selection.
Duran's breakout was largely driven by harder, more consistent contact—his barrel rate spiked from the 20th percentile to the 63rd. As a result, his xSLG (.453) and xwOBA (.342) made big jumps while his xBA stayed roughly the same. His strikeout rate and walk rate also both improved.
One of the most encouraging aspects of all this was that Duran's BABIP actually from .381 in 2023 to .345 in ’24. That's still very high, but his speed gives him a leg up on converting batted balls into base hits. Duran has all the ingredients to continue being a star in Boston.
3B Mark Vientos, New York Mets
The Mets shocked a lot of people with their run to the NLCS in 2024, which Vientos’s emergence played a significant part in. A '17 second-round pick, Vientos was a bit of a late bloomer as a prospect, coming into his own as a 24-year-old last season. He flashed much brighter than he had in 81 games spent in the bigs the previous two years, slashing .266/.322/.516 with 27 home runs and 71 RBIs in 111 games. His OPS (.837) and OPS+ (135) marks were second on the Mets behind only Francisco Lindor (.844, 138) among full-time players.
Part of Vientos's jump had to do with his BABIP jumping to .324 from .264 in 2023. He has, however, always produced solid exit velocities, as he was at 93.3 in 2022, 92.5 in ’23 and 91.2 in ’24. That said, he was more consistent last year, as his barrel rate jumped into the 92nd percentile.
Vientos is expected to be a huge part of the Mets' offense moving forward, combining with Lindor, Juan Soto, Pete Alonso and Brandon Nimmo in what should be a strong top half of the lineup. Expect some regression in 2025—it’d be surprising if he again led National League third basemen in OPS (min. 450 plate appearances)—but the underlying metrics show he can hit the ball well at the MLB level.
SP Ronel Blanco, Houston Astros
Blanco opened the season recording an expansion-era record 44 outs before allowing a hit—not a bad way to start things off. He was then suspended for 10 days for having a sticky substance on his glove during a May 14 start, but that didn't derail his season. In what was the 31-year-old's first full big league campaign he went 13–6 with a 2.80 ERA, a 1.09 WHIP and 166 strikeouts in 167 1/3 innings. Like Gil, Blanco came into 2024 with just seven MLB starts, but he ended it as a cornerstone of the Astros' rotation.
Blanco's sudden rise reflected improvements across the board. His average exit velocity dropped to 88.7 mph, while his hard-hit rate was only 35.5%. His xBA dropped from .245 to .226, and his xFIP improved from 5.12 to 4.09 as he stunningly led the majors with just 6.1 hits allowed per nine innings. Blanco clearly emphasized inducing soft contact over racking up whiffs, as his ground ball rate jumped from 34.7% to 39.9%. That could be attributed to an increased use of his changeup, which was the seventh-best in MLB last season according to Stuff+. He threw it 22.2% of the time in 2024 as compared to 8.9% in ’23 while dialing down usage of his slider, which made both pitches more effective.
Given the wide gulf between Blanco's xFIP (4.09) and his ERA (2.80), it's fair to assume there will be some regression here. A pitcher reliant on soft contact can’t be expected to prevent base hits as effectively as Blanco did last year. But if his arsenal remains as balanced as it was in 2024, he should still put up good numbers.