There are a lot of things that go into successfully managing a fantasy baseball team. One of the least obvious, yet most important, is having trust in your players to perform when you need them to.

However, if a player who no one expected to do well suddenly starts performing like a superstar, that player is almost certainly engaging in trickery and mischief with the intention of causing your fantasy empire to crumble.

That’s why you must work the waiver wire cautiously. Here are five players who are doing well right now that I believe are due for major regressions.

[media-credit name=”undefined | Daily Nexus” align=”alignright” width=”140″][/media-credit]Bartolo Colon, SP, New York Yankees: 2 wins, 3.86 ERA, 37 strikeouts

I’m sorry to those of you who like a good comeback story, but asking me to believe that big, fat Bartolo Colon can come back after being out of the league for two years and maintain a 37 to seven strikeout-to-walk ratio and a 1.23 WHIP is too much. The last time he pitched a full season was back in 2005, when he posted a 1.16 WHIP and a 3.48 ERA. Since then, he has not been able to log more than 99.1 innings in a season and has managed an ERA under four just once, when he pitched seven games for Boston in 2008. Maybe this is the second coming of Bartolo, but I think he is going to start to regress, and soon.

Bud Norris, SP, Houston Astros: 2 wins, 3.16 ERA, 52 strikeouts

This is only Norris’ third season in the majors, so he may be reaching his potential, but it just seems too drastically different from his previous two seasons, in which he posted very similar stats. His ERA is almost two runs lower than it was last season, and his 52 strikeouts put him on pace to far exceed the 158 he posted in 27 starts a year ago. Add that to a lower walk rate, and you get a player who seems to have reinvented himself in the course of one offseason. Like I said, he may have simply found his stride, but I would be very surprised if he didn’t end the season with an ERA a lot closer to four.

Matt Joyce, OF, Tampa Bay Rays: .356 AVG, 3 HR, 14 RBI

Joyce’s current stats are so out of line with what he posted in his previous three seasons that the only possible conclusion is that he is riding a very long hot streak. Joyce is a career .262 hitter and has never hit for an average higher than .252 before this season. Similarly, his current OPS (.956), slugging percentage (.554) and on-base percentage (.356) are much higher than anything he’s posted before. He’s due to come back down to earth soon, and the fall could hit owners who trusted him very hard indeed.

Russell Martin, C, New York Yankees: .255 AVG, 6 HR, 20 RBI

For those of you who picked Martin up when he was hitting over .300 and are holding on to him in case he brings his average back up, forget it. Martin has not hit over .250 since 2008. His on-base percentage (.358) is also settling into the area that it has been in for the last three seasons. The only thing that’s keeping him a viable option is his .500 slugging percentage, but that’s due to come down as well, as the last time he even slugged better than .400 was 2007.

Daisuke Matsuzaka, SP, Boston Red Sox: 3 wins, 24 strikeouts, 4.64 ERA

Daisuke has allowed two or fewer runs in four of his last five starts (though one of those was only one inning) and has started to walk fewer batters. However, he let up four runs in six innings in his last start and two runs in a one inning appearance against the Angels four days earlier. He has posted an ERA under 4.40 once in his career with the Red Sox, and I believe that his ERA will settle about where it is for the rest of the season. If you picked him up thinking that he was going to keep throwing gems like the one he threw against the Angels on April 23 or against the Blue Jays on April 18, you are out of luck.

Daily Nexus fantasy sports columnist Josh Greenberg likes lists. They’re neat and organized. If you don’t like it, YOU write the column.