The season is still a few months away, but fantasy baseball is a year-long mistress that requires constant attention. Here, for the upcoming week, are the five storylines you should be following:

Oft-injured Los Angeles Angels of Anaheim infielder Dallas McPherson had spinal infusion surgery this past week to take care of chronic back pain the 26-year-old has been experiencing for two years. The Los Angeles Times reports that the procedure "will sideline the young Angels slugger for at least six months but should bring a considerable amount of relief to his aching lower back and frayed psyche." McPherson was a popular sleeper pick in fantasy drafts last year as the highly-touted youngster was projected by many to have a breakout year. His fantasy value plummets as McPherson's recovery period figures to take him at least into August and may cause him to miss the entire 2007 season. First basemen Casey Kotchman and Kendry Morales and second baseman Howie Kendrick each figure to benefit from McPherson's absence. All three of these players are skilled and were top prospects for the Angels franchise, so check to see if there are any updates on who gets a bump up on the depth chart since their fantasy value would figure to rise as well.

The Philadelphia Phillies are currently entering the 2007 season with an improved starting pitching rotation and the same potent offense. But the bullpen looks thin and that's where starter Jon Lieber comes in. The Philadelphia Inquirer is reporting that the Phillies "expect to trade righthanded starter Jon Lieber at some point. That trade could provide the biggest boost to the bullpen." Philadelphia has 2006 All-Star Tom Gordon as their closer. But after that, the bullpen consists of newly signed reliever Antonio Alfonseca, Geoff Geary, Ryan Madson, Matt Smith and perhaps one or two players in their farm system. Judging from the shape of their relieving corps, Philadelphia would be wise to deal Lieber for a relief arm. Lieber, an All-Star in 2001 with the Chicago Cubs when he won 20 games, was limited by injury last year. For fantasy purposes, Lieber will likely not make a great impact. But a trade for bullpen help will aid Gordon, who labored through the second half of last season after enviable stats in April and May. Gordon, with this current bullpen, stands to see multiple innings per outing and that will likely drain his stuff as the season progresses, makings his numbers suffer. Follow this story to see if the Phillies pull the trigger on a deal, especially if it significantly helps their bullpen and Gordon.

New York Yankees starting pitcher Carl Pavano hasn't exactly lived up to expectations since the Yankees gave him a four-year deal worth just under $40 million. In fact, the New York Post is reporting that the Yankees have "fielded calls from clubs wanting to know if Pavano is available...if Pavano pitches effectively in the exhibition season the Yankees may see what they can get for the injury-prone righthander." Pavano hasn’t pitched in a big league game since June 2005 and he wasn't effective when pitching in pinstripes. He's thrown all of 100 innings with a 4-6 record and a 4.77 ERA. He cashed in after an All-Star season in 2004 with the Florida Marlins, where he posted an 18-8 record and a 3.00 ERA. If he could approach those numbers again — as a Yankee or elsewhere — his fantasy value would certainly skyrocket. Of course, his injury history raises red flags about treating him as a reliable fantasy pitching option. Pavano threw a bullpen session this past week and his rehab is supposedly going well. If you were drafting today, you should stay as far away from Pavano as possible. Monitor this story as he could develop into a decent sleeper pick if he continues to improve.

Injuries have prevented Oakland Athletics shortstop Bobby Crosby from developing into the fantasy star many expected him to be. Now, going into the 2007 season, his health is again becoming a major concern for the A's. The San Francisco Chronicle is reporting that new manager Bob Geren "is not sure that shortstop Bobby Crosby, who is recovering from a stress fracture in his back, will [be] completely ready until the end of spring training." The report also reveals that the team may limit Crosby until he is fully healed. After winning the American League Rookie of the Year award in 2004, Crosby missed 78 games in 2005 and 66 games in 2006. He has the talent to be a top fantasy shortstop, but he has to prove that he can stay healthy and consistent. Follow up on this story to see how Crosby progresses. If he can enter the season with a clean bill of health, he would certainly at least merit sleeper status.

Colorado Rockies first baseman Todd Helton has garnered five All-Star Game appearances, a batting title, 286 home runs and a .333 career batting average playing for the Rockies during his entire pro tenure. But despite being the face of the franchise, rumors persist that Helton may be on his way out of Coors Field. ESPN.com is reporting that "the Rockies are in high-level talks to trade Helton to the Red Sox." This trade would be a boon to Helton's fantasy value as he would go from one of the weakest lineups in baseball to one of the most potent. While Helton's season numbers have declined over the past two seasons — 2005 marked the first time he hit less than 30 home runs and had fewer than 100 runs since 1998 — a lot of his troubles last year can be attributed to a stomach virus that sapped his strength greatly during the season. That being said, Helton has hit over .300 every season since his rookie campaign and a change of scenery may be just what he needs to reawaken the skills that made him an elite first basemen in the fantasy realm. A deal could happen any day.