What's more impressive: A 24-year-old posting a 2.27 ERA while striking out 191 batters over 178 1/3 innings? Or a 38-year-old posting a 1.09 ERA over 74 1/3 regular-season innings before closing out a World Series?
Matt Harvey vs. Koji Uehara figures to be one of the top debates for Major League Baseball's best breakout pitcher in the 2013 Greatness in Baseball Yearly (GIBBY) Awards.
Major League Baseball's A-listers will take home 2013 GIBBY trophies -- the ultimate honor of the industry's awards season -- based on votes by media, front-office personnel, MLB alumni, fans at MLB.com and the Society for American Baseball Research.
This year's GIBBY Awards feature nominees in 22 categories. Individual honors will go to the MLB MVP, in addition to the year's best starting pitcher, hitter, closer, setup man, rookie, breakout hitter, breakout pitcher, comeback player, defensive player, manager, executive and postseason performer.
GIBBY trophies also will be awarded for the year's top play, storyline, hitting performance, pitching performance, oddity, walk-off, Cut4 topic, regular-season moment and postseason moment, from MLB.com's Must C highlight reels.
In the past five years, fans have cast more than 50 million votes across the various GIBBY categories, none of which was restricted to individual league affiliation. Fan voting runs through Dec. 1.
Winners will be presented their GIBBY trophies at the MLB.com Greatness in Baseball Yearly Awards extravaganza during the Winter Meetings in Lake Buena Vista, Fla.
R.A. Dickey took home the award for breakout pitcher in 2012, while Ian Kennedy captured the honors in 2011.
In 2013, Harvey and Uehara lead an impressive list that also includes Andrew Cashner, Patrick Corbin, Hisashi Iwakuma, Mike Minor, Chris Tillman and Travis Wood.
Harvey, who underwent Tommy John surgery on Oct. 22, might have been a lock for the award prior to September. He had allowed three hits or less in eight of his 24 starts before an elbow injury forced him to shut down early.
"Here's my thought: going into this year, you knew Harvey was going to be good," Mets third baseman David Wright said earlier this month. "You didn't know Harvey was going to be flat-out dominant. It was a bonus that he became flat-out dominant."
But Harvey made his last start on Aug. 24, and that's when Uehara went on a run. A closer in Japan, Uehara had limited experience in the role during his Major League career, but he was thrust into ninth-inning duties as the Red Sox's "fourth option," manager John Farrell said. Joel Hanrahan and Andrew Bailey were both lost to season-ending injuries, and Junichi Tazawa was later stripped of the job. Given the chance, Uehara was nearly perfect.
He retired 37 batters in a row during a run in September. He saved 21 games in the regular season before his seven saves in the postseason tied the Major League record.
"Every time he walks to the mound," Farrell said, "it's one of the most calm innings that we'll watch, regardless of the stage, regardless of the importance of the game."
If there's a dark-horse candidate, it might be Iwakuma, the second-year Mariners pitcher who made drastic improvements from his rookie season. Iwakuma pitched 219 2/3 innings for Seattle, going 14-6 with a 2.66 ERA and 185 strikeouts. For his work, Iwakuma ousted Felix Hernandez for the award of Mariners Pitcher of the Year, presented by the Seattle Chapter of the Baseball Writers' Association of America.
Had he not slowed down in the second half, Corbin might've been a front-runner. His 2013 statistics were still nothing short of impressive, as he posted a 3.41 ERA over 208 1/3 innings while earning his first appearance in the All-Star Game. But his 2.35 ERA in the first half, compared to a 5.19 ERA in the second half, left the Diamondbacks hopeful of an even brighter future.
"Just didn't have the same pitches he had in the first half," manager Kirk Gibson said. "I'm sure part of it had to do with how far he went; we asked a lot of him. He made 32 starts -- that's a lot in the big leagues for such a young kid. It just caught up to him a bit. I know he'll be better; he'll get stronger."
Minor was the No. 2 pitcher on the Braves' staff in the postseason, but his numbers were ace-worthy. The 25-year-old lefty lowered his ERA nearly a full run from 2012 to 2013, posting a 3.21 ERA over 204 2/3 innings with a strikeout-to-walk rate of 3.93.
"I don't really have dominant stuff," Minor said. "I don't throw 95 [mph]. But I don't really care. I don't really care what people call me, if they call me an ace or they call me a No. 5. If I go out there and win ballgames, then nobody cares."
Wood didn't have the strikeout numbers of his competitors, but he increased his ground-ball rate while decreasing his home run rate on his way to 200 brilliant innings with a 3.11 ERA.
Cashner, a first-round Draft pick in 2008, was traded from the Cubs to the Padres in 2012 in the deal that sent first baseman Anthony Rizzo to Chicago. In his first year as a full-time starter, the hard-throwing righty put up an impressive 3.09 ERA over 175 innings. His 2.14 second-half ERA should give the Padres hope for even better year in 2014.
Tillman's breakout might have been predictable, after he started to put it together in 2012, making 15 starts with a 2.93 ERA. In 2013, he showed similar signs of progress, striking out a career-high 7.8 per nine innings while posting a 3.71 ERA over 206 1/3 innings for the Orioles.
Jason Mastrodonato is a reporter for MLB.com. Follow him on Twitter @jmastrodonato.