In 1992, David Nied changed baseball history.
Called up by the Braves for a September trial, Nied proceeded to give up just 10 hits in 23 innings, post a 1.17 ERA and advertise himself as one of the Braves' most promising arms. So promising that when Atlanta left him available in that November's expansion draft, the Rockies jumped all over him with the first overall pick.
Nied's great month didn't last -- he flamed out pretty quickly -- but the ultimate disappointment, it turns out, could be that his September mound debut doesn't even rank among the top 10 in baseball history.
Some kept up their dominance, some disappeared. Still more used that first big-league shot to make an immediate and indelible difference on the pennant race:
10. Roy Halladay, 1998 Blue Jays
The Jays' top pitching prospect, Halladay got pretty much lit by the expansion Devil Rays in his major league debut that September. But his second start one week later gave a hint of the Cy Young Award winner to come. Pitching against Detroit, Halladay stood one out away from a no-hitter when Bobby Higginson hit a solo home run. Halladay still won the game 2-1.
9. Steve Busby, 1972 Royals
Kansas City had a bunch of good young pitchers through the 1970s -- Paul Splittorff and Dennis Leonard among them -- but none looked as good as early as Busby. A former College World Series hero for Southern Cal, Busby reached the big leagues after just one full minor league season and immediately gave the Royals a taste of what was to come: He went 3-1, 1.58 and gave up just 28 hits in 40 innings. (And just before the DH came to the American League, he stroked a grand slam that was wiped out when the umpire said he had called time.) Busby stayed just as hot in '73 and '74, pitching no-hitters each season, but a string of injuries ultimately kept him from developing into the longtime star many expected.
8. Larry Jaster, 1965 Cardinals
A hard-throwing bonus baby known as "the Creeper" because he was so quiet, Jaster made a plenty loud debut in September 1965. He went 3-0, 1.61 in four appearances, completing all three of his starts. Making the St. Louis roster the following spring training, Jaster followed up with an 11-5, 3.26 season -- highlighted by five shutouts, all against the pennant-winning Dodgers.
7. Randy Johnson, 1988 Expos
In 1988, Johnson wasn't supposed to be a September callup -- the Expos planned to promote him in June from Triple-A Indianapolis before he broke his right hand punching a bat rack. Montreal finally got its first look at the 6-foot-10 prodigy in the season's final month, when he went 3-0, 2.42 in four starts, including a 9-1, 11-strikeout, complete-game win over the Cubs. Most encouragingly, the wild left-hander walked just seven batters in 26 innings. But Johnson wasn't ready yet -- his poor control landed him back in the minors the following spring, and we haven't heard from the guy since.
6. Nick Maddox, 1907 Pirates
A 20-year-old right-hander who had already thrown two no-hitters for the Central League's Wheeling club, Maddox twirled a 4-0 shutout over St. Louis in his first major league start for Pittsburgh that September -- and didn't slow down. One week later, he no-hit Brooklyn. He finished 5-1, 0.83 to earn a spot in the rotation the following year. Maddox made good on it, going 23-8 in 1908 and in 1909 helping the powerhouse Pirates to 110 wins and the World Series championship. Amazingly, Maddox was out of the majors only one season later.
5. Harry Coveleski, 1907 Phillies
We're cheating a bit here, but you'll soon see why. In 1907, Coveleski made a great September debut for the Phillies, pitching 20 shutout innings in four relief appearances. Perhaps not good enough to make this list. But the next year, Coveleski came up in September again, and all but decided the National League pennant race. Coveleski got four wins in five starts with a 1.24 ERA; with several of his starts thwarting the Giants' attempt to win the NL pennant, Coveleski earned the lasting nickname "The Giant Killer."
4. Fernando Valenzuela, 1980 Dodgers
The Fernandomania of 1981 caught many people by surprise, but he'd already given plenty of hints the previous September that he was something special. Pitching in relief at age 19 -- at least we think he was just 19 -- Valenzuela threw 17 2/3 shutout innings over 10 games, allowing just eight hits. It only got better, of course. After the winter, he finally did give up a run: only one in his first five starts of 1981, four of them shutouts and all of them wins. Fernandomania was born.
3. Karl Spooner, 1954 Dodgers
A top prospect summoned from Double-A Fort Worth -- where the hard-throwing left-hander led the Texas League with 21 wins and 262 strikeouts -- Spooner got only two starts after his callup to Brooklyn, and made spectacular success of both. On Sept. 22 he threw a 3-0 shutout over the Giants, striking out 15, six of them in a row. Four days later, on the last day of the season, Spooner blanked the Pirates 1-0 for two shutouts in two tries -- and was rewarded with an appearance on the Ed Sullivan Show. With incredible expectations entering 1955, Spooner hurt his arm that spring training, and never pitched in the majors again after the '55 World Series. Brooklynites still wonder what mighta been.
2. Francisco Rodriguez, 2002 Angels
After starting the season at Double-A Arkansas, Rodriguez made his major league debut on the late date of Sept. 18 but was so dominant in just 5 2/3 innings -- he gave up three hits with a ridiculous 13 strikeouts -- that the Angels used a loophole to add him to their postseason roster. Good move: Rodriguez made 11 appearances in the playoffs and World Series, going 5-1 with a 1.93 ERA with just 15 baserunners in 18 2/3 innings of stultifying middle relief. Almost certainly, Anaheim wouldn't have won the World Series without him.
1. Marty Bystrom, 1980 Phillies
The Phillies were a half-game back of the Expos on Sept. 10, 1980, when they inserted Bystrom, just a few days removed from his major league debut, into their rotation for the stretch drive. He proceeded to make all the difference: Bystrom shut out the Mets in that first start and won four of his others to go 5-0 with a 1.50 ERA, getting the Phillies to squeak past the Expos by just one game and win the NL East. Bystrom also started both Game 5s in the NLCS and World Series, and though he wasn't credited with wins, helped the Phillies win both games and, ultimately, their first World Series championship. Sadly, injuries kept Bystrom from being anywhere near as effective again, and he was out of the majors after 1985. His was September stardom at its best.
Alan Schwarz is the senior writer of Baseball America and a regular contributor to ESPN.com. His new book, "The Numbers Game: Baseball's Lifelong Fascination With Statistics," is published by St. Martin's Press and can be ordered on Alan's Web site.