The first week on the waiver wire shows why a fantasy owner must be vigilant in improving his or her roster from day one. One team has already made a change at closer (more on that in a bit), and two more could be on the horizon. A big-time pitching prospect made his presence felt in his major league debut, and a few old friends reminded the fantasy community how they can be useful in our universe. You may have just drafted your team two weeks ago, but chances are there's already a move that can make your roster even better.
? RP Kyuji Fujikawa, Cubs: Congratulations if you selected April 7 in a "When will Carlos Marmol lose his job as the Cubs closer?" pool. After surrendering the coolest-ever game-tying and walk-off homers in major league history to the Upton brothers, Marmol was ousted from the closer's chair in favor of Fujikawa. The MLB rookie has an impressive résumé in Japan, where he saved 202 games and posted a 1.36 ERA, 0.86 WHIP and 510 strikeouts in 369.2 innings across six seasons. Fujikawa struggled against the Braves on Saturday, and the Cubs may not provide him with a ton of save chances, but we don't discriminate based on such circumstances in the fantasy community. Fujikawa is getting the ball in the ninth for the Cubs until further notice, and we have no reason to believe he won't be a success. Get him while you can.
? SP Jose Fernandez, Marlins: The 20-year-old Fernandez shined in his major league debut Sunday, allowing just one run on three hits and one walk, while striking out eight Mets. Fernandez, the 14th overall pick in the 2011 First-Year Player Draft, dominated hitters at Low-A Greensboro and High-A Jupiter last year. He went 14-1 at the two levels combined, posting a 1.59 ERA, 1.78 FIP and 11.28 K/9 at Greensboro. At Jupiter, he had a 1.96 ERA, 2.15 FIP and 9.65 strikeouts per nine innings. Now that the Marlins have already started his service clock, it's hard to see them sending him down to the minors at any point this season. This is a high upside play, and I'd grab him in all but the shallowest of leagues. Basically, if your league is at least 12 teams deep, someone should own Fernandez. Might as well be you.
? OF Nate McLouth, Orioles: McLouth is off to a decent start at the plate, going 5-for-19 in the season's first week. However, he can really help fantasy owners on the basepaths, where he has already swiped two bags this season. Buck Showalter turned McLouth loose after the Orioles picked him up last year, and McLouth stole 12 bases in just 55 games with Baltimore. Showalter has him at the top of what looks like it could be a very strong offense, giving McLouth ample opportunity to steal bases and score runs. He could end up being a very cheap source of 90-100 runs and 20 steals, and now's a great time to buy in on him.
? C Tyler Flowers, White Sox: Flowers is off to a quick start in his first year as the starter behind the dish for the White Sox, going 5-for-15 with a pair of homers. He's already 27 and hasn't played more than 52 games in a major league season, but he showed decent pop throughout his minor league career. In 673 career at-bats at Triple-A Charlotte, he hit 33 homers and drove in 98 runs. He's not going to help your rates much, but he could be a nice source of power.
? SS Zack Cozart, Reds: Like Flowers, Cozart isn't going to be of much assistance in your rate categories. However, he blasted two homers on Friday, and should end up among the league leaders for home runs by a shortstop. Whether or not you can afford to add Cozart will have a lot to do with your roster composition. If you're already carrying a few players who are batting average or OBP sinkholes, you can't really grab Cozart. But if you're strong in those categories and in need of another power bat, Cozart might be your man. He could hit 20 homers, especially playing half his games at Great American Ballpark.