Dozens of new players have arrived on major-league rosters since the calendar turned over to September last week. Many of them are marginal prospects or journeymen roster-filler, but there are occasional gems you should be aware of. Here's a look at some National League callups, focusing primarily on those players with long-term potential. Note that some teams will call up more people once the minor-league playoffs are over.

Arizona
Mike Koplove, Alex Cintron, Jack Cust, Lyle Overbay, Eric Knott
Knott and Koplove aren't super prospects, but both could be useful middle relievers. There are a lot of guys like that around; why teams fart around with people like Doug Henry is beyond me. Cintron is a great prospect according to scouts, who like his raw athleticism and defense at shortstop. He looks like a .260-.270 hitter with little power and a low on-base percentage at this stage, so his production may never match his hype. Both Cust and Overbay are left-handed hitters blocked by Mark Grace and Erubiel Durazo. Cust has more power, while Overbay is more of a batting average/doubles guy. I wouldn't be afraid to give either one a major-league job next year, though it may not happen in Arizona.

Atlanta
Tim Spooneybarger, Corey Aldridge, Damian Moss
Aldridge has great tools, but he hit just .246 in Double-A this year and his strike zone judgment is abysmal. Avoid him. I like Moss as a versatile lefty with a decent arm, but he has trouble staying healthy at times, which is my big fear for his future. Spooneybarger posted a 0.50 ERA at Triple-A Richmond, and is ready for a middle-relief job in the majors. His control isn't great, but he gets nasty movement on his pitches and is tough for right-handed hitters to pick up. He's allowed just three home runs in 156 career innings.

Chicago
Juan Cruz, Chad Meyers
Meyers spent parts of 2000 and 1999 with the major-league team. He's a useful bench guy when he has his stroke in gear; he gets in trouble when he tries too hard to hit for power, but does best when he concentrates on working the count and getting on base to make his speed valuable. Cruz kicks butt; he has a great arm and is possibly the most talented of a large group of pitching prospects in the Cubs system. He's done very well so far but I think he may need a half year of Triple-A before being completely ready. His command is still a problem at times, although it hasn't hurt his performance so far. He is a premium pitching prospect and fantasy owners should grab him if available.

Cincinnati
Calvin Pickering, Chris Piersoll
Now, this is interesting. The Reds have liberated Pickering from the Orioles. He slammed 21 homers and hit .282 for Triple-A Rochester this year. It will be hard to find him consistent at-bats, but at least he's getting a change of scenery, and I still think he'll hit if he gets a chance and stays healthy. Piersoll saved 19 for Double-A Chattanooga, but is unlikely to take a closer role in the majors. Like many of these guys, he could be a useful middle man. He keeps the ball down, and I like his 78 strikeouts in 56 innings.

Colorado
Todd Belitz, Jason Jennings
Belitz draws some notice because he came over in the three-way Jermaine Dye/Neifi Perez/Jose Ortiz deal with Oakland and Kansas City, but his upside is as an anti-lefty middle man. Jennings threw a shutout and hit a home run in his major-league debut in late August, and has a 1.23 ERA in his first three starts. I would give him a strong recommendation for fantasy owners if he pitched for any team but the Rockies. I think he's a fine pitcher, with good stuff and very sharp command, though he'll have to fight his environment.

Florida
Josh Beckett, Kevin Olsen, Jason Grilli, Blaine Neal
So, the Glorious Josh Beckett Era has begun. He is every bit as good as people say, but I estimate that there is a 78.564 percent chance that he will suffer a serious arm injury within two years. He is the perfect pitching prospect, with fireball stuff plus good control, but he's had some minor arm troubles already, and most pitchers his age get hurt pretty badly at some point. His presence overshadows control artist Olsen, former first-round pick Grilli, and potential middle reliever Neal. Odds are one of that trio will have a good career, though your guess is as good as mine as to which one.

Houston
Tim Redding, Adam Everett, Carlos Hernandez
Redding has a 5.79 ERA in eight games for the Astros, but I think his long-term potential is every bit as good as Roy Oswalt's. He is a sound investment, at least as pitchers go. Hernandez has been brilliant since coming up in mid-August. He'll slump at some point, but as a live-armed lefty he'll have a long career, assuming that injuries don't become a problem. Everett is a slick gloveman at shortstop with good speed, but he has a career .247 average in two Triple-A seasons. Hopes that he would improve with the bat appear to have been misplaced, as he has actually regressed in some ways. I doubt he'll ever hit enough to be a regular for a rational team.

Los Angeles
Jeff Williams, McKay Christensen
The Dodgers called up several guys like Phil Hiatt and Brian Johnson. About the only interesting possible long-termers are Williams and Christensen, and I don't see either as more than marginal performers. Williams is a Nosferatu lefty, while Christensen could make a decent reserve outfielder due to his lefty stick, speed, and defense.

Milwaukee
Alex Sanchez, Brandon Kolb
Cuban defector and Devil Rays castoff Sanchez is interesting if you like speed. He has a lefty stick, runs like the wind, and occasionally hits one into the gaps. He isn't patient but does make decent contact; he is another guy looking for a bench job. Kolb has saved 30 games in two years, but looks to be a 11th man on most pitching staffs.

Montreal
Brad Wilkerson
Best hope in the outfield for the Expos now that Milton Bradley is gone and Pete Bergeron is nearly an official bust. Wilkerson has more plate discipline in his left toe than most Expos hitters have in their whole bodies, but he takes time to adjust to each level. I think he'll hit if they just leave him alone and let him figure it out, but excessive tinkering could screw him up.

New York
Jorge Toca
The shine is off his Cuban star; he's proven to be a mediocre line-drive hitter who won't hit for a high batting average in the major leagues or draw enough walks to make up for it.

Philadelphia
Doug Nickle, Eric Valent
Nickle has a better chance to make it than most minor-league closers. His stuff is legitimate, and if he can refine his control a hair more, he'll have a long career as a middle man. Valent struggled in his initial exposure, but he does have enough power to be an OK regular. The pinch-hitting role he currently "enjoys" is not well-suited for him, however. He needs to get in a groove and coming off the bench hurts that aspect of his game.

Pittsburgh
Humberto Cota, Chad Hermansen, Ryan Vogelsong
Cota is a catch-and-throw guy who developed some power this year. He won't start in Pittsburgh, but I think he can be a solid reserve backstop, and should have a 10-year career once he gets his reputation established. Hermansen should be the face of a public service announcement about plate discipline: THIS IS YOUR CAREER IF YOU DON'T CONTROL THE STRIKE ZONE. Vogelsong is a major hope for the Pirates future, over from the Giants in the Jason Schmidt deal. He is being counted on to fill a starting slot next year, so look at September as an early audition.

San Diego
Junior Herndon, Jason Middlebrook, Mike Colangelo, Kevin Witt, Wascar Serrano
An eclectic group. Colagelo can hit for average but is physically fragile; he'll have some good games but is hard to count on in anything more than a pinch-hitting role, and you know what kind of job security that gives him. Witt can crush the ball, but he walked just 22 times with 127 strikeouts in Triple-A. Ick. Middlebrook has a live arm and pitched very well this year, but this is the first year he's been completely healthy since the reign of George III. He could be a surprise if bullpen work keeps his arm from falling off. Herndon is a soft-tosser with the guts of a drill instructor, but sometimes that isn't enough. Hopefully he won't end up like the drill instructor in Full Metal Jacket. Serrano is someone I've liked for several years. He hasn't been especially impressive this year, but I still believe in him. Maybe I'm just stubborn.

San Francisco
Jalal Leach, Damon Minor, Cody Ransom, Kurt Ainsworth, Ryan Jensen
We profiled Ainsworth in Down on the Farm this week. He's a great prospect despite his 5-plus ERA this year. Jensen has decent stuff and a 3.65 ERA in six starts for the Giants, but I hate his 22/23 K/BB ratio. Watch for him to crash and burn at some point, though maybe not until next spring. Ransom is a great athlete with a good glove at shortstop, but his offense is very inconsistent due to weak strike zone judgment. I would avoid getting excited about him. Damon Minor is a better hitter than his brother Ryan, but he isn't so good that he'll force any starting first baseman out of his job. Leach is a 32-year old minor-league vet finally getting a chance to play. I root for him and he hits enough to be marginally useful off the bench.

St. Louis
Stubby Clapp, Luis Saturria, Bud Smith
I don't have to write about Bud Smith here, since he's played enough in the majors to be more than a "callup" but I just wanted to mention him. I don't have a problem with his pitch count in the no-hitter, provided that they ease up on his workload the rest of the season. He'll be John Tudor if he stays healthy. Clapp has a terrific name, hustles, and hits just enough to be useful as a bench guy. There are a lot of guys like that in Triple-A. Saturria has great tools, and if he had Clapp's ability to play baseball he'd be a superstar. As it is, he'd hit about .200 in the majors with a horrible on-base percentage.

John Sickels is the author of the 2001 STATS Minor League Scouting Notebook. He lives in Lawrence, Kansas, with his wife, son, and two cats. You can send John questions or comments at JASickels@aol.com, or you can visit his homepage at hometown.aol.com/jasickels/page1.html.